feat(web): mark sessions linked to a Mattermost chat

apps/server/src/environment/ServerEnvironment.ts

@@ -159,6 +159,8 @@ export const make = Effect.gen(function* () {
       threadPriority: true,
       // T3-CUSTOM(expbkt3): durable manual Linear tags.
       threadLinearIssue: true,
+      // T3-CUSTOM(expbkt3): durable Mattermost conversation link.
+      threadMattermostLink: true,
       threadExternalSessionAttach: true,
       // T3-CUSTOM(expbkt3): high-level durable bootstrap and defaults hierarchy.
       durableThreadBootstrap: true,

apps/server/src/orchestration/Layers/ProjectionPipeline.ts

@@ -762,6 +762,8 @@ const makeOrchestrationProjectionPipeline = Effect.fn("makeOrchestrationProjecti
             priority: event.payload.priority ?? null,
             // T3-CUSTOM(expbkt3): no manual Linear tag at thread creation.
             linearIssueUrl: null,
+            // T3-CUSTOM(expbkt3): the Mattermost link is bound after creation.
+            mattermostThreadUrl: null,
             // T3-CUSTOM(expbkt3): session lineage stamped at creation.
             parentThreadId: event.payload.parentThreadId ?? null,
             // T3-CUSTOM(expbkt3): BEGIN — no work summary until one is requested.
@@ -1040,6 +1042,10 @@ const makeOrchestrationProjectionPipeline = Effect.fn("makeOrchestrationProjecti
             ...(event.payload.linearIssueUrl !== undefined
               ? { linearIssueUrl: event.payload.linearIssueUrl }
               : {}),
+            // T3-CUSTOM(expbkt3): durable Mattermost conversation link.
+            ...(event.payload.mattermostThreadUrl !== undefined
+              ? { mattermostThreadUrl: event.payload.mattermostThreadUrl }
+              : {}),
             // T3-CUSTOM(expbkt3): session lineage re-parent / detach.
             ...(event.payload.parentThreadId !== undefined
               ? { parentThreadId: event.payload.parentThreadId }

apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts

@@ -349,6 +349,8 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
           priority: null,
           // T3-CUSTOM(expbkt3): no manual Linear tag on this fixture.
           linearIssueUrl: null,
+          // T3-CUSTOM(expbkt3): no Mattermost conversation on this fixture.
+          mattermostThreadUrl: null,
           // T3-CUSTOM(expbkt3): session lineage.
           parentThreadId: null,
           // T3-CUSTOM(expbkt3): no work summary was ever requested here.
@@ -501,6 +503,8 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
           priority: null,
           // T3-CUSTOM(expbkt3): no manual Linear tag on this fixture.
           linearIssueUrl: null,
+          // T3-CUSTOM(expbkt3): no Mattermost conversation on this fixture.
+          mattermostThreadUrl: null,
           // T3-CUSTOM(expbkt3): session lineage.
           parentThreadId: null,
           // T3-CUSTOM(expbkt3): no work summary was ever requested here.

apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts

@@ -592,6 +592,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON blob).
           work_summary AS "workSummary",
@@ -680,6 +681,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON blob).
           work_summary AS "workSummary",
@@ -731,6 +733,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON blob).
           work_summary AS "workSummary",
@@ -1191,6 +1194,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON blob).
           work_summary AS "workSummary",
@@ -1263,6 +1267,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON blob).
           work_summary AS "workSummary",
@@ -2228,6 +2233,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                 snoozedAt: row.snoozedAt,
                 priority: row.priority,
                 linearIssueUrl: row.linearIssueUrl ?? null,
+                mattermostThreadUrl: row.mattermostThreadUrl ?? null,
                 parentThreadId: row.parentThreadId ?? null,
                 // T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary.
                 workSummary: mapWorkSummary(row.workSummary),
@@ -2548,6 +2554,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                   snoozedAt: row.snoozedAt,
                   priority: row.priority,
                   linearIssueUrl: row.linearIssueUrl ?? null,
+                  mattermostThreadUrl: row.mattermostThreadUrl ?? null,
                   parentThreadId: row.parentThreadId ?? null,
                   // T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary.
                   workSummary: mapWorkSummary(row.workSummary),
@@ -2733,6 +2740,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                         snoozedAt: row.snoozedAt,
                         priority: row.priority,
                         linearIssueUrl: row.linearIssueUrl ?? null,
+                        mattermostThreadUrl: row.mattermostThreadUrl ?? null,
                         parentThreadId: row.parentThreadId ?? null,
                         // T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary.
                         workSummary: mapWorkSummary(row.workSummary),
@@ -2924,6 +2932,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                     snoozedAt: row.snoozedAt,
                     priority: row.priority,
                     linearIssueUrl: row.linearIssueUrl ?? null,
+                    mattermostThreadUrl: row.mattermostThreadUrl ?? null,
                     parentThreadId: row.parentThreadId ?? null,
                     // T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary.
                     workSummary: mapWorkSummary(row.workSummary),
@@ -3257,6 +3266,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
         snoozedAt: threadRow.value.snoozedAt,
         priority: threadRow.value.priority,
         linearIssueUrl: threadRow.value.linearIssueUrl ?? null,
+        mattermostThreadUrl: threadRow.value.mattermostThreadUrl ?? null,
         parentThreadId: threadRow.value.parentThreadId ?? null,
         // T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary.
         workSummary: mapWorkSummary(threadRow.value.workSummary),
@@ -3492,6 +3502,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
         snoozedAt: threadRow.value.snoozedAt,
         priority: threadRow.value.priority,
         linearIssueUrl: threadRow.value.linearIssueUrl ?? null,
+        mattermostThreadUrl: threadRow.value.mattermostThreadUrl ?? null,
         parentThreadId: threadRow.value.parentThreadId ?? null,
         // T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary.
         workSummary: mapWorkSummary(threadRow.value.workSummary),

apps/server/src/orchestration/decider.priority.test.ts

@@ -214,4 +214,60 @@ it.layer(NodeServices.layer)("thread priority decider", (it) => {
       ).toBeNull();
     }),
   );
+
+  // T3-CUSTOM(expbkt3): the Mattermost conversation a session is bound to.
+  it.effect("sets and clears a Mattermost link through thread metadata", () =>
+    Effect.gen(function* () {
+      const linked = yield* decideOrchestrationCommand({
+        command: {
+          type: "thread.meta.update",
+          commandId: CommandId.make("cmd-link-mattermost"),
+          threadId: ThreadId.make("thread-1"),
+          mattermostThreadUrl: "https://chat.example.com/beknown/pl/abc123",
+        },
+        readModel: makeReadModel(),
+      });
+      const linkedEvents = Array.isArray(linked) ? linked : [linked];
+      expect(
+        linkedEvents[0]?.type === "thread.meta-updated"
+          ? linkedEvents[0].payload.mattermostThreadUrl
+          : undefined,
+      ).toBe("https://chat.example.com/beknown/pl/abc123");
+
+      const cleared = yield* decideOrchestrationCommand({
+        command: {
+          type: "thread.meta.update",
+          commandId: CommandId.make("cmd-clear-mattermost"),
+          threadId: ThreadId.make("thread-1"),
+          mattermostThreadUrl: null,
+        },
+        readModel: makeReadModel(),
+      });
+      const clearedEvents = Array.isArray(cleared) ? cleared : [cleared];
+      expect(
+        clearedEvents[0]?.type === "thread.meta-updated"
+          ? clearedEvents[0].payload.mattermostThreadUrl
+          : undefined,
+      ).toBeNull();
+    }),
+  );
+
+  it.effect("leaves the Mattermost link untouched when the command omits it", () =>
+    Effect.gen(function* () {
+      const event = yield* decideOrchestrationCommand({
+        command: {
+          type: "thread.meta.update",
+          commandId: CommandId.make("cmd-rename-only-mattermost"),
+          threadId: ThreadId.make("thread-1"),
+          title: "Renamed",
+        },
+        readModel: makeReadModel(),
+      });
+      const events = Array.isArray(event) ? event : [event];
+      if (events[0]?.type === "thread.meta-updated") {
+        // undefined, not null: an omitted field must not clear a live binding.
+        expect(events[0].payload.mattermostThreadUrl).toBe(undefined);
+      }
+    }),
+  );
 });

apps/server/src/orchestration/decider.ts

@@ -928,6 +928,10 @@ export const decideOrchestrationCommand = Effect.fn("decideOrchestrationCommand"
           ...(command.linearIssueUrl !== undefined
             ? { linearIssueUrl: command.linearIssueUrl }
             : {}),
+          // T3-CUSTOM(expbkt3): undefined leaves the Mattermost link unchanged.
+          ...(command.mattermostThreadUrl !== undefined
+            ? { mattermostThreadUrl: command.mattermostThreadUrl }
+            : {}),
           // T3-CUSTOM(expbkt3): undefined leaves lineage unchanged; null detaches.
           ...(command.parentThreadId !== undefined
             ? { parentThreadId: command.parentThreadId }

apps/server/src/orchestration/projector.test.ts

@@ -104,6 +104,8 @@ describe("orchestration projector", () => {
         priority: null,
         // T3-CUSTOM(expbkt3): no manual Linear tag on a new thread.
         linearIssueUrl: null,
+        // T3-CUSTOM(expbkt3): no Mattermost conversation bound to a new thread.
+        mattermostThreadUrl: null,
         // T3-CUSTOM(expbkt3): session lineage.
         parentThreadId: null,
         deletedAt: null,

apps/server/src/orchestration/projector.ts

@@ -353,6 +353,8 @@ export function projectEvent(
             priority: payload.priority ?? null,
             // T3-CUSTOM(expbkt3): no manual Linear tag at thread creation.
             linearIssueUrl: null,
+            // T3-CUSTOM(expbkt3): the Mattermost link is bound after creation.
+            mattermostThreadUrl: null,
             // T3-CUSTOM(expbkt3): session lineage stamped at creation.
             parentThreadId: payload.parentThreadId ?? null,
             deletedAt: null,
@@ -528,6 +530,10 @@ export function projectEvent(
             ...(payload.linearIssueUrl !== undefined
               ? { linearIssueUrl: payload.linearIssueUrl }
               : {}),
+            // T3-CUSTOM(expbkt3): durable Mattermost conversation link.
+            ...(payload.mattermostThreadUrl !== undefined
+              ? { mattermostThreadUrl: payload.mattermostThreadUrl }
+              : {}),
             // T3-CUSTOM(expbkt3): session lineage re-parent / detach.
             ...(payload.parentThreadId !== undefined
               ? { parentThreadId: payload.parentThreadId }

apps/server/src/persistence/Layers/ProjectionThreads.ts

@@ -54,6 +54,7 @@ const makeProjectionThreadRepository = Effect.gen(function* () {
           snoozed_at,
           priority,
           linear_issue_url,
+          mattermost_thread_url,
           parent_thread_id,
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON).
           work_summary,
@@ -94,6 +95,7 @@ const makeProjectionThreadRepository = Effect.gen(function* () {
           ${row.snoozedAt},
           ${row.priority},
           ${row.linearIssueUrl ?? null},
+          ${row.mattermostThreadUrl ?? null},
           ${row.parentThreadId ?? null},
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON).
           ${row.workSummary ?? null},
@@ -134,6 +136,7 @@ const makeProjectionThreadRepository = Effect.gen(function* () {
           snoozed_at = excluded.snoozed_at,
           priority = excluded.priority,
           linear_issue_url = excluded.linear_issue_url,
+          mattermost_thread_url = excluded.mattermost_thread_url,
           parent_thread_id = excluded.parent_thread_id,
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON).
           work_summary = excluded.work_summary,
@@ -181,6 +184,7 @@ const makeProjectionThreadRepository = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON).
           work_summary AS "workSummary",
@@ -230,6 +234,7 @@ const makeProjectionThreadRepository = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           -- T3-CUSTOM(expbkt3): BEGIN — bulk session manager work summary (JSON).
           work_summary AS "workSummary",
@@ -288,6 +293,7 @@ const makeProjectionThreadRepository = Effect.gen(function* () {
           snoozed_at AS "snoozedAt",
           priority,
           linear_issue_url AS "linearIssueUrl",
+          mattermost_thread_url AS "mattermostThreadUrl",
           parent_thread_id AS "parentThreadId",
           work_summary AS "workSummary",
           pinned_at AS "pinnedAt",

apps/server/src/persistence/Migrations.ts

@@ -67,6 +67,7 @@ import Migration1005 from "./Migrations/036_ProjectionThreadsPinned.ts";
 // T3-CUSTOM(expbkt3): fork migrations, numbered 1000+.
 import Migration1000 from "./Migrations/1000_ProjectionThreadsPriority.ts";
 import Migration1022 from "./Migrations/1022_AgentUiRenders.ts";
+import Migration1023 from "./Migrations/1023_ProjectionThreadsMattermostLink.ts";
 import Migration1001 from "./Migrations/1001_SessionRecoveryState.ts";
 import Migration1002 from "./Migrations/1002_ThreadBootstrapAndCreationDefaults.ts";
 // T3-CUSTOM(expbkt3): exact durable work items and guarded recovery audit.
@@ -226,6 +227,8 @@ const migrationEntries = [
   [1021, "ProjectionThreadsUnsettledAt", Migration1021],
   // T3-CUSTOM(expbkt3): agent-rendered UI surfaces in chat.
   [1022, "AgentUiRenders", Migration1022],
+  // T3-CUSTOM(expbkt3): durable Mattermost conversation link on a thread.
+  [1023, "ProjectionThreadsMattermostLink", Migration1023],
 ] as const;
 
 export const migrationManifest = migrationEntries.map(([id, name]) => [id, name] as const);

apps/server/src/persistence/Migrations/1023_ProjectionThreadsMattermostLink.test.ts

@@ -0,0 +1,25 @@
+// T3-CUSTOM(expbkt3): durable Mattermost conversation link migration coverage.
+import { assert, it } from "@effect/vitest";
+import * as Effect from "effect/Effect";
+import * as Layer from "effect/Layer";
+import * as SqlClient from "effect/unstable/sql/SqlClient";
+
+import { runMigrations } from "../Migrations.ts";
+import * as NodeSqliteClient from "../NodeSqliteClient.ts";
+
+it.layer(Layer.mergeAll(NodeSqliteClient.layerMemory()))(
+  "1023_ProjectionThreadsMattermostLink",
+  (it) => {
+    it.effect("adds the nullable Mattermost conversation URL", () =>
+      Effect.gen(function* () {
+        const sql = yield* SqlClient.SqlClient;
+        yield* runMigrations({ toMigrationInclusive: 1023 });
+
+        const columns = yield* sql<{ readonly name: string }>`
+          PRAGMA table_info(projection_threads)
+        `;
+        assert.isTrue(columns.some((column) => column.name === "mattermost_thread_url"));
+      }),
+    );
+  },
+);

apps/server/src/persistence/Migrations/1023_ProjectionThreadsMattermostLink.ts

@@ -0,0 +1,20 @@
+// T3-CUSTOM(expbkt3): durable Mattermost conversation permalink on a thread.
+// Written by the Linear/Mattermost bridge when it binds a session to a
+// Mattermost thread, so the sidebar can mark sessions a human is watching
+// from chat. Nullable: most threads have no Mattermost conversation.
+import * as Effect from "effect/Effect";
+import * as SqlClient from "effect/unstable/sql/SqlClient";
+
+export default Effect.gen(function* () {
+  const sql = yield* SqlClient.SqlClient;
+  const columns = yield* sql<{ readonly name: string }>`
+    PRAGMA table_info(projection_threads)
+  `;
+
+  if (!columns.some((column) => column.name === "mattermost_thread_url")) {
+    yield* sql`
+      ALTER TABLE projection_threads
+      ADD COLUMN mattermost_thread_url TEXT
+    `;
+  }
+});

apps/server/src/persistence/Services/ProjectionThreads.ts

@@ -53,6 +53,8 @@ export const ProjectionThread = Schema.Struct({
   priority: Schema.NullOr(ThreadPriority),
   // T3-CUSTOM(expbkt3): durable manual Linear issue URL.
   linearIssueUrl: Schema.optional(Schema.NullOr(Schema.String)),
+  // T3-CUSTOM(expbkt3): durable Mattermost conversation permalink.
+  mattermostThreadUrl: Schema.optional(Schema.NullOr(Schema.String)),
   // T3-CUSTOM(expbkt3): session lineage; null means this is a root session.
   parentThreadId: Schema.optional(Schema.NullOr(ThreadId)),
   // T3-CUSTOM(expbkt3): BEGIN — JSON-encoded ThreadWorkSummary for the bulk session