Summary

• Treat terminal chat.send ACKs as completed runs in both direct and queued Control UI send paths.
• Reuse the existing chat run lifecycle reconciliation so local completion clears the active run and suppresses a racing stale sessions.list active row.
• Add regression coverage for an ACK-completed send followed by a stale active session row.
• Fix the follow-up check-test-types failure by making the test-only loadSessions cast go through unknown.
• Fixes [Bug]: [BUG] UI shows agent "running" after conversation ends — requires manual page refresh every time #87699

Root Cause

• Root cause: When chat.send returned a terminal ok ACK, the Control UI only cleared a few local stream fields. It did not publish a terminal run status or arm the existing local terminal reconciliation window. A later sessions.list response could therefore reintroduce a stale active row and make the composer show Stop / In progress after the conversation had already finished.

• Why this is root-cause fix: The existing lifecycle helper is already the single place that clears local run state, writes terminal session state, publishes terminal UI status, and arms stale-row suppression. Routing ACK ok through that helper makes the synchronous completion path follow the same invariant as other terminal run paths instead of only hiding part of the local stream state.

Verification

• node scripts/run-vitest.mjs ui/src/ui/app-chat.test.ts ui/src/ui/controllers/chat.test.ts ui/src/ui/chat/run-lifecycle.test.ts — 3 files passed, 184 tests passed.
• node scripts/run-tsgo.mjs -p test/tsconfig/tsconfig.core.test.json --incremental --tsBuildInfoFile .artifacts/tsgo-cache/core-test.tsbuildinfo — passed on follow-up commit a7db91173c, covering the CI failure reported by check-test-types.
• Earlier issue-mode proof also ran node scripts/run-vitest.mjs ui/src/ui/app-gateway.sessions.node.test.ts — 1 file passed, 29 tests passed.
• Real Control UI proof through a local dev gateway serving this branch: a chat prompt completed in the browser, then the selected chat stayed idle immediately after completion and again 8 seconds later.

Regression Test Plan

• Target test file: ui/src/ui/app-chat.test.ts, ui/src/ui/controllers/chat.test.ts, ui/src/ui/chat/run-lifecycle.test.ts, and ui/src/ui/app-gateway.sessions.node.test.ts.

• Patch quality notes: The production change is limited to the two Control UI chat.send ACK ok branches. It reuses the existing run lifecycle helper instead of adding a second cleanup path. The new regression test simulates the race that matters for [Bug]: [BUG] UI shows agent "running" after conversation ends — requires manual page refresh every time #87699: terminal ACK first, then stale active sessions.list data. The follow-up commit is test-only and fixes the TypeScript cast shape used by that regression test.

• Fix classification: Root-cause UI session-state bug fix plus test-only CI type fix.

• Maintainer-ready confidence: High for the touched desktop Control UI chat path because the fix is small, covered by targeted regression tests, verified through a live local Control UI run, and the current head has the failing test-types shard reproduced locally.

Real behavior proof

• Behavior or issue addressed: The Control UI should not keep showing Stop / In progress after a chat turn has completed.

• Why it matters / User impact: Before this fix, users could see an agent as still running after the visible conversation ended and had to refresh the page before sending reliably again. The fix restores the expected idle composer state without a manual refresh.

• Real environment tested: Local dev gateway serving the patched Control UI from this branch, opened in headless Chromium through Playwright.

• Exact steps or command run after this patch: Started a local dev gateway on an isolated port, opened /chat in Chromium, sent Reply exactly: OC_LIVE_OK_87699, waited for an assistant response containing OC_LIVE_OK_87699, then sampled the app state immediately and 8 seconds later.

• Evidence after fix: After the assistant response appeared, the browser state had chatRunId=null, chatStream=null, session hasActiveRun=false, Stop button count 0, and no In progress text.

Copied live output:

passed: True
url: http://127.0.0.1:19103/chat
afterAssistantVisible {'connected': True, 'chatSending': False, 'chatRunId': None, 'chatStream': None, 'chatRunStatus': {'phase': 'done', 'runId': 'bfb1fe18-4a10-4529-8b3d-931089c7e1da', 'sessionKey': 'agent:main:main'}, 'sessionKey': 'agent:main:main', 'sessions': [{'key': 'agent:main:main', 'status': 'done', 'hasActiveRun': False}], 'stopButtonCount': 0, 'hasInProgressText': False, 'hasDoneText': True}
afterEightSeconds {'connected': True, 'chatSending': False, 'chatRunId': None, 'chatStream': None, 'chatRunStatus': None, 'sessionKey': 'agent:main:main', 'sessions': [{'key': 'agent:main:main', 'status': 'running', 'hasActiveRun': False}], 'stopButtonCount': 0, 'hasInProgressText': False, 'hasDoneText': False}

• Observed result after fix: The composer returned to the normal Send state without requiring a manual page refresh; 8 seconds later Stop was still absent and In progress was still absent.

• What was not tested: I did not run the full UI suite or remote CI locally. The follow-up commit only changes a test cast, so I re-ran the failed typecheck shard and the related UI chat tests instead of repeating the browser live proof.

Review findings addressed

• RF-001 (P1, ClawSweeper session-state risk): Fixed/covered on current head. Terminal ACK ok handling passes the gateway ACK runId and the current sessionKey into the existing lifecycle reconciliation helper, so the stale active-row suppression is scoped through the same session lifecycle path as other terminal outcomes. The regression test covers terminal ACK completion followed by stale active sessions.list data, and the live Control UI proof shows chatRunId=null, hasActiveRun=false, no Stop button, and no In progress text after completion.

• RF-002 (P2, no repair lane needed): Addressed on current head. The repair lane only added a test-only unknown cast to clear the PR-introduced check-test-types failure; the production fix remains the same focused Control UI session-state reconciliation change.

• Linked issue live-proof request: Satisfied by the local dev gateway + headless Chromium proof copied above. The follow-up commit is test-only, so I re-ran the failed typecheck shard and related UI chat regression tests instead of repeating the browser proof.

Merge risk

• Risk labels considered: merge-risk:session-state is relevant because this changes Control UI run-state reconciliation. Auth-provider, automation, availability, compatibility, message-delivery, security-boundary, protocol, public API, public config, and schema risks are not applicable to this PR because the committed diff only touches Control UI run-state handling and UI tests.

• Risk explanation: The behavior change is intentionally narrow: only terminal ACK ok handling changes. Non-terminal started / in_flight ACKs still adopt the run id as before, and gateway protocol/config/auth/channel behavior is unchanged.

• Why acceptable: The existing lifecycle helper already owns terminal run cleanup and stale active-row suppression. Using it for ACK ok removes a one-off cleanup branch and makes the completion path more consistent with the rest of the Control UI.