fix(server): avoid completed-item scans when starting turns

apps/server/src/orchestration-v2/ProjectionStore.test.ts

@@ -3115,7 +3115,30 @@ it.layer(layerTest)("ProjectionStoreV2", (it) => {
       assert.include(recoveryThreadIds, childThreadId);
       assert.notInclude(recoveryThreadIds, settledThreadId);
       assert.notInclude(recoveryThreadIds, rolledBackThreadId);
-      const memberRecovery = yield* projectionStore.getRuntimeRecoveryProjection(memberThreadId);
+      const { statements, tracer } = traceSqlStatements();
+      const memberRecovery = yield* projectionStore
+        .getRuntimeRecoveryProjection(memberThreadId)
+        .pipe(Effect.withTracer(tracer));
+      // Completed history grows without bound, so the provider-thread read's
+      // unfinished-item lookups must stay on a partial index.
+      const providerThreadRead = statements.find((query) =>
+        query.includes("SELECT provider_thread.payload_json"),
+      );
+      assert.isDefined(providerThreadRead);
+      const sql = yield* SqlClient.SqlClient;
+      const itemLookups = (yield* sql.unsafe<{ readonly detail: string }>(
+        `EXPLAIN QUERY PLAN ${providerThreadRead}`,
+      ))
+        .map((row) => row.detail)
+        .filter((detail) => /^(SEARCH|SCAN) item /.test(detail));
+      assert.isNotEmpty(itemLookups);
+      for (const detail of itemLookups) {
+        const indexName = /INDEX (\S+)/.exec(detail)?.[1] ?? "";
+        const [index] = yield* sql<{ readonly sql: string }>`
+          SELECT sql FROM sqlite_master WHERE type = 'index' AND name = ${indexName}
+        `;
+        assert.match(index?.sql ?? "", /WHERE[\s\S]*status/, detail);
+      }
       const childRecovery = yield* projectionStore.getRuntimeRecoveryProjection(childThreadId);
       assert.deepEqual(
         memberRecovery.subagents.map((subagent) => subagent.id),

apps/server/src/persistence/Migrations.ts

@@ -70,6 +70,7 @@ import Migration0064 from "./Migrations/064_CanonicalizeThreadPullRequestLinks.t
 import Migration0065 from "./Migrations/065_CodexUsageNativeTurnIndex.ts";
 import Migration0066 from "./Migrations/066_RepairClientSettlementTimestamps.ts";
 import Migration0067 from "./Migrations/067_WebhookDedupe.ts";
+import Migration0068 from "./Migrations/068_UnfinishedTurnItemsIndex.ts";
 
 const migrationEntries = [
   [1, "OrchestrationEvents", Migration0001],
@@ -140,6 +141,7 @@ const migrationEntries = [
   [65, "CodexUsageNativeTurnIndex", Migration0065],
   [66, "RepairClientSettlementTimestamps", Migration0066],
   [67, "WebhookDedupe", Migration0067],
+  [68, "UnfinishedTurnItemsIndex", Migration0068],
 ] as const;
 
 export const migrationManifest = migrationEntries.map(([id, name]) => [id, name] as const);

apps/server/src/persistence/Migrations/068_UnfinishedTurnItemsIndex.ts

@@ -0,0 +1,14 @@
+import * as Effect from "effect/Effect";
+import * as SqlClient from "effect/sql/SqlClient";
+
+export default Effect.gen(function* () {
+  const sql = yield* SqlClient.SqlClient;
+
+  // Recovery's provider-thread read looks up unfinished items of any type, which
+  // the type-filtered recovery index cannot serve.
+  yield* sql`
+    CREATE INDEX orchestration_v2_projection_turn_items_unfinished_idx
+    ON orchestration_v2_projection_turn_items(thread_id)
+    WHERE status IN ('pending', 'running', 'waiting')
+  `;
+});

apps/server/src/persistence/reconcileV2PreviewMigration.test.ts

@@ -47,6 +47,7 @@ describe("V2 preview upgrade", () => {
         [65, "CodexUsageNativeTurnIndex"],
         [66, "RepairClientSettlementTimestamps"],
         [67, "WebhookDedupe"],
+        [68, "UnfinishedTurnItemsIndex"],
       ]);
       assert.deepStrictEqual(yield* runMigrations(), []);
       assert.deepStrictEqual(yield* sql`SELECT * FROM orchestration_v2_legacy_imports`, imports);
@@ -137,6 +138,7 @@ describe("V2 preview upgrade", () => {
         [65, "CodexUsageNativeTurnIndex"],
         [66, "RepairClientSettlementTimestamps"],
         [67, "WebhookDedupe"],
+        [68, "UnfinishedTurnItemsIndex"],
       ]);
     }).pipe(Effect.provide(NodeSqliteClient.layer({ filename: ":memory:" }))),
   );