fix(desktop): stabilize Runtime Host Session lifecycle races

apps/desktop/e2e/quote-companion.spec.ts

@@ -709,7 +709,7 @@ test('side chat recovers from failures and preserves its draft', async ({
     failPanel.getByText(/Fake backend received: retry after deterministic network failure/),
   ).toBeVisible();
 
-  await failComposer.fill('__e2e_error__:auth');
+  await failComposer.fill('__e2e_wait_for_steering__');
   await failComposer.press('Enter');
   const activeSideTab = page.locator(
     '.maka-workbar-tab[data-running][data-workbar-tab-id^="side-chat:"]',
@@ -722,7 +722,6 @@ test('side chat recovers from failures and preserves its draft', async ({
   await expect
     .poll(async () => (await page.evaluate(() => window.maka.sessions.list())).length)
     .toBe(1);
-  await expect(page.getByText('鉴权失败')).toHaveCount(0);
 
   // Draft survival across collapse and launcher navigation.
   await waitForSourceSessionToSettle(page);

apps/desktop/src/main/__tests__/quote-companion-core.test.ts

@@ -17,6 +17,7 @@ import {
   applyCompanionInteractionEvent,
   cleanupCompanionCopy,
   createCompanionDismissalGuard,
+  dismissCompanionCopy,
   companionRunEventEffect,
   deriveCompanionComposerState,
   isCompanionTurnTerminal,
@@ -58,6 +59,7 @@ interface FakeControl {
 
 function makeApi(control: FakeControl = {}) {
   const calls = {
+    lifecycle: [] as string[],
     removed: [] as string[],
     sent: [] as {
       id: string;
@@ -95,13 +97,17 @@ function makeApi(control: FakeControl = {}) {
       return forked;
     },
     cleanupSessionCopy: async (id) => {
+      calls.lifecycle.push(`cleanup:${id}`);
       calls.removed.push(id);
       if (control.cleanupThrows) throw new Error('cleanup failed');
     },
     abandonSessionCopy: async (id) => {
       calls.abandoned.push(id);
       if (control.abandonThrows) throw new Error('abandon acknowledgement lost');
     },
+    stop: async (id) => {
+      calls.lifecycle.push(`stop:${id}`);
+    },
     send: async (id, cmd) => {
       calls.sent.push({ id, cmd });
       if (control.sendThrows) throw new Error('send failed');
@@ -172,6 +178,19 @@ describe('companion dismissal guard', () => {
     assert.equal(replayedCleanup(), false);
     assert.equal(activeCleanup(), true);
   });
+
+  it('stops a live companion before dismissing its durable copy', async () => {
+    const { api, calls } = makeApi();
+
+    assert.equal(
+      await dismissCompanionCopy(api, 'source-session', 'panel-1', 'companion-session'),
+      true,
+    );
+    assert.deepEqual(calls.lifecycle, [
+      'stop:companion-session',
+      'cleanup:companion-session',
+    ]);
+  });
 });
 
 describe('deriveCompanionComposerState', () => {

apps/desktop/src/main/__tests__/runtime-host-client-operations.test.ts

@@ -211,6 +211,35 @@ test('merges a configuration patch into each fresh CAS projection', async () =>
   );
 });
 
+test('retries a Session update through transient revision churn', async () => {
+  const responses: unknown[] = [];
+  for (let revision = 10; revision < 14; revision += 1) {
+    responses.push(
+      { kind: 'session', session: session('session-1', revision) },
+      {
+        kind: 'revision_conflict',
+        expectedRevision: revision,
+        actualRevision: revision + 1,
+      },
+    );
+  }
+  responses.push(
+    { kind: 'session', session: session('session-1', 14) },
+    {
+      kind: 'committed',
+      session: session('session-1', 15, { collaborationMode: 'plan' }),
+    },
+  );
+  const { client } = clientWithResponses(responses);
+
+  const updated = await client.updateSessionConfiguration('session-1', {
+    collaborationMode: 'plan',
+  });
+
+  assert.equal(updated.revision, 15);
+  assert.equal(updated.collaborationMode, 'plan');
+});
+
 test('rebuilds a Runtime Policy mutation from each fresh CAS projection', async () => {
   const initial = createDefaultRuntimePolicy();
   const concurrent = {

apps/desktop/src/main/runtime-host-client.ts

@@ -97,6 +97,7 @@ import {
 } from "@maka/runtime-host/protocol";
 
 const MAX_OPTIMISTIC_ATTEMPTS = 3;
+const MAX_SESSION_REVISION_ATTEMPTS = 8;
 const MAX_PRICING_SNAPSHOT_ATTEMPTS = 3;
 
 export type DesktopSessionConfigurationPatch = Partial<SessionConfiguration>;
@@ -730,7 +731,7 @@ export class DesktopRuntimeHostClient {
   }
 
   async removeSession(sessionId: string): Promise<void> {
-    for (let attempt = 0; attempt < MAX_OPTIMISTIC_ATTEMPTS; attempt += 1) {
+    for (let attempt = 0; attempt < MAX_SESSION_REVISION_ATTEMPTS; attempt += 1) {
       const current = await this.#requireSession(sessionId);
       const result = await this.#request("session.remove", {
         sessionId,
@@ -1379,7 +1380,7 @@ export class DesktopRuntimeHostClient {
     sessionId: string,
     update: (current: SessionCatalogProjection) => Promise<SessionUpdateResult>,
   ): Promise<SessionCatalogProjection> {
-    for (let attempt = 0; attempt < MAX_OPTIMISTIC_ATTEMPTS; attempt += 1) {
+    for (let attempt = 0; attempt < MAX_SESSION_REVISION_ATTEMPTS; attempt += 1) {
       const current = await this.#requireSession(sessionId);
       const result = await update(current);
       if (result.kind === "committed")

apps/desktop/src/renderer/quote-companion-core.ts

@@ -48,6 +48,7 @@ export interface CompanionSessionApi {
   ): Promise<SessionSummary>;
   cleanupSessionCopy(sessionId: string): Promise<void>;
   abandonSessionCopy(sessionId: string): Promise<void>;
+  stop(sessionId: string): Promise<void>;
   send(
     sessionId: string,
     command: {
@@ -170,6 +171,16 @@ export async function cleanupCompanionCopy(
   }
 }
 
+export async function dismissCompanionCopy(
+  api: CompanionSessionApi,
+  sourceSessionId: string,
+  panelId: string,
+  companionSessionId: string,
+): Promise<boolean> {
+  await api.stop(companionSessionId).catch(() => undefined);
+  return cleanupCompanionCopy(api, sourceSessionId, panelId, companionSessionId);
+}
+
 /**
  * The shared Composer's `streaming` input means "a turn is interruptible", not
  * merely "a text delta has arrived". Keep the companion interruptible from the

apps/desktop/src/renderer/use-quote-companion.ts

@@ -24,8 +24,8 @@ import type { RendererIngestInput } from '../preload/bridge-contract.js';
 import {
   abandonPendingCompanionCopy,
   applyCompanionInteractionEvent,
-  cleanupCompanionCopy,
   createCompanionDismissalGuard,
+  dismissCompanionCopy,
   companionRunEventEffect,
   deriveCompanionComposerState,
   ensureCompanionFork,
@@ -307,7 +307,7 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
         const sourceSessionId = sourceSessionIdRef.current;
         const id = companionIdRef.current ?? pendingForkIdRef.current;
         if (id && sourceSessionId) {
-          void cleanupCompanionCopy(
+          void dismissCompanionCopy(
             window.maka.sessions,
             sourceSessionId,
             panelId,