Greptile Summary

This PR makes two focused, targeted fixes to the typing indicator system: (1) it suppresses the tool-start typing indicator on silent message runs (where NO_REPLY is returned) in message/thinking modes by adding a pre-text guard in signalToolStart, and (2) it prevents the keepalive loop from being re-armed when onIdle/onCleanup closes the controller while a start() call is still in-flight by adding || closed to the post-fireStart guard.

Key changes:

• src/channels/typing.ts: adds || closed check after await fireStart() in onReplyStart() — fixes the keepalive re-arm race condition
• src/auto-reply/reply/typing-mode.ts: adds early-return in signalToolStart when mode is not instant, typing is not active, and no renderable text has been seen — suppresses typing on silent tool-only runs
• All three test files add targeted coverage for the new behaviors with clear, well-isolated test cases

Confidence Score: 5/5

• This PR is safe to merge — both fixes are minimal, well-scoped, and covered by new tests.
• Both changes are single-concern fixes with clear before/after semantics. The || closed guard in typing.ts plugs a well-understood async race without touching any other logic. The guard added to signalToolStart in typing-mode.ts is additive (early return only) and its three conditions are each individually tested. New tests cover the exact race condition and the mode-specific tool-start behavior. No pre-existing tests appear to be broken by the behavioral changes.
• No files require special attention.

_{Last reviewed commit: 6d46dff}