* fix(annotate): watch open source files exactly
* test(annotate): cover atomic watcher saves
* fix(watch): survive atomic file replacement
* fix(watch): disable exact-file coalescing
* fix(watch): track exact file signatures
* fix(annotate): tolerate undefined watcher filenames and harden watch callbacks
The exact-file watcher only treated a `null` filename as "name unavailable".
On Linux, Bun's fs.watch delivers `filename === undefined` for events on the
watched directory itself (chmod/utimes/rename of the parent, as produced by
`tar -x`, `rsync -a`, `cp -a`), so `filename.toString()` threw an uncaught
TypeError and killed the annotate server for every Linux user with a watched
file open.
Widen the guard to `filename == null` (null and undefined) and move the
listener into `createExactFileWatchListener`, whose body is wrapped in
try/catch so no watcher event can ever take the server down. Mirrored in the
Pi runtime, with regression tests in both.
Claude-Session: https://claude.ai/code/session_01H5KQWqXqjrPxyxUNso1QHS
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Co-authored-by: Michael Ramos <mdramos8@gmail.com>
Raúl