[teamleaderleo]

Fix for the independent UX-04 / MODE-06 review of #28634

Stacked on #28634 (base lane/orch-agent-pane-hunt2 at 8de2d9a420735128268066946dd3b02667b08e5e), preserving its original owner and branch. This is a small, reviewable correction for the head-pinned P2 finding; do not merge or rebase it independently of #28634.

What changed

• AgentRunTranscriptCard wraps the existing standalone AgentRunCard in TranscriptDisclosureProvider with the real VirtualTranscript.sessionId. The prior fallback __transcript__ persisted all standalone agent-run expansions globally.
• SubagentGroupRow passes its session ID into the wrapper and includes it in its memo equality so switching chats cannot reuse stale state.
• Added a negative regression: chats A, B and C with the same run:call-1 ID keep independent Show more choices, including an unmount/remount. The test uses the exported wrapper that production now uses, and deliberately omits any test-only disclosure provider.

Evidence and acceptance

• This branch has three changed files and five commits atop fix(agent-pane): remember expanded sub-session result text #28634, verified by GitHub compare: 5/4 line diff in App.tsx, 10-line wrapper, and 41-line test.
• Code/test commit: 82af5bc3bd11981e557e1eaccc7bd2e82ea87ba0.
• Tests have not been run in this connected GitHub session (no local checkout/fleet). This is a draft pending webviews test CI, typecheck, independent review, and optional exact-head UI capture. Suggested focused command on an authorized runner: cd webviews && bun test test/subsession-disclosure.test.tsx.
• Acceptance: A expanded → B collapsed on same run call ID → B expanded → A stays expanded across virtualization → new chat C starts collapsed; existing ordinary sub-session disclosure tests remain green.
• Performance: No perf numbers: the change adds one local React context provider per standalone run card and one cheap memo comparison; no polling, background work, measurement or new timer.

Ownership and release

Please review/land this scoped correction through #28634's existing implementation owner; target branch of this PR is the original feature lane, not feat-cmux-next. Do not merge #28634 before its separate existing red perf-description gate and other hold/CI issues are cleared or attributed. This PR requests no app/production rollout.

HQ dispatch: https://github.com/manaflow-ai/cmuxterm-hq/issues/5457#issuecomment-6536783040.

[blacksmith-sh]

Found 8 test failures on Blacksmith runners:

Failures

Test	View Logs
---/---	View Logs
---/---	View Logs
test/browser/gallery-control-surfaces.test.ts/gallery-control-surfaces.test	View Logs
test/browser/gallery-control-surfaces.test.ts/gallery-control-surfaces.test	View Logs
test/browser/gallery-control-surfaces.test.ts/gallery-control-surfaces.test	View Logs
test/gallery-coverage.test.ts/gallery-coverage.test	View Logs
test/gallery-coverage.test.ts/gallery-coverage.test	View Logs
test/gallery-coverage.test.ts/gallery-coverage.test	View Logs

^{Need help on this PR? Tag @codesmith-bot with what you need.}

[cmux-bot]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Probably yours: gallery-coverage.test.ts fails here but not on main's latest full suite. Seen on other PRs too (likely flaky): gallery-control-surfaces.test.ts, gallery-coverage.test.ts.

CI failed on 82af5bc3bd (run 41154638114 attempt 1): 1 code, 1 unknown.

Job	Verdict	Why
web / react-apps-check (1)	code	a web test failed
web / react-apps-check	unknown	no known signature; failed step: Check webview test shards

Failures:

• seen on other PRs gallery-control-surfaces.test.ts every web gallery entry keeps trailing surfaces clear and hover inside its control: failed (job)
• seen on other PRs gallery-coverage.test.ts gallery coverage > every cover names a component or page that exists: failed (job)
• new in this PR gallery-coverage.test.ts gallery coverage > the allowlist names only what is still missing: failed (job)

Matched log lines

web / react-apps-check (1): (fail) every web gallery entry keeps trailing surfaces clear and hover inside its control [110329.96ms]

Not re-run automatically: web / react-apps-check (1), web / react-apps-check are not machine failures.

Written by scripts/ci/classify_failures.py (ci-failure-attribution.yml); signatures are its SIGNATURES table. A machine verdict is the runner's fault, not this PR's; yours means the failing file is one this PR changes, also red on main that main's latest full suite fails the same way, seen on other PRs that it failed on another pull request's run lately.

CI fast guards failed on 82af5bc3bd (https://github.com/manaflow-ai/cmux/actions/runs/41154638114). It does not block the merge; a red guard merged into main breaks it for every open PR.
The log named no failed step; see the run.

Agents: python3 scripts/ci/guard_attribution.py fix applies the mechanical fixes locally.

[teamleaderleo]

Awareness note from an agent lane that does not own this PR; it is not a review or a request to take the PR over.

---

Carried to #31544 for Leo's ask ask-e06a62154f, together with #28634, which this draft was stacked on. The cherry-pick conflicted in the test file against base's rewritten "started sub-session" test; that is resolved there, and there are no code changes vs this draft. This draft can be closed once #31544 lands.