AIDA-1977: Preserve replies after failed sends

[ngthuydiem]

Summary

When a Desktop send fails, its rollback restores an earlier conversation snapshot. Messages received while that send was pending disappear, and overlapping sends can erase or resurrect each other.

Remove only the failed send's optimistic row from the current timeline and channel window. Preserve incoming messages, separate thread caches, history pages, and other pending sends.

Related issue

Partial fix for AIDA-1977. This addresses messages that arrive and then disappear after a failed send. It does not change how agents publish final answers.

Closest related work: #7249, which proposes harness publication of Activity-only answers and touches a different path.

Testing

Built Desktop with its isolated mock bridge, held an outgoing send, delivered an incoming result, then released a terminal relay rejection. The result disappears on the base build. The fixed build preserves it through rejection and navigation in both repetitions.

Command: pnpm build:e2e && pnpm exec playwright test --project=smoke failed-send-preserves-replies.spec.ts --repeat-each=2.

Validated in Chromium on macOS with synthetic accounts and a mock relay. Native Windows and a real agent/relay reconnect were not exercised.

Before: incoming result disappears

After: incoming result remains

Known validation gaps

The full local just ci run is not green: it stopped at ACP unit tests outside this Desktop change. The inherited owner-only configuration explains one failure; timing and steering failures remain unresolved. Native runtime acceptance remains pending.

Generated with Codex

[github-actions]

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