## Why
Keep diagnostics accessible without adding warning rows to the live conversation or changing the composer layout.
## What changed
- Show a deduplicated warning count in the passive footer, yielding to interactive hints.
- Open warning details with `F2`, `/warnings`, or a click on the warning notice. Support navigation, scrolling, and copying individual diagnostics while preserving the draft.
- Retain startup, runtime, MCP, and deprecation diagnostics in the full transcript. Group MCP details by server and preserve warnings during replay.
- Respect existing custom bindings and chord prefixes when enabling `F2`.
- Show an immediate explanation when `/pets` is unavailable.
## Testing
Add regression tests and snapshots for warning counts, draft preservation, viewer navigation and copying, narrow layouts, terminal scrollback, and keybinding conflicts.
GitOrigin-RevId: 2bc586430da60347cfbaa5bf128bc48f7f9dc777
Eric Traut
6b0a1a8325