Prior attempt accepted either fs.watch failure path (sync throw vs async
error event) — but on Linux Node, fs.watch with `recursive: true` on a
missing directory silently succeeds (returns a no-op watcher, never
throws, never emits an error). Neither catch arm fires, so the warning
the test wants to assert never appears.
Switch to a NUL-byte-embedded path. Node validates the path argument up
front and throws ERR_INVALID_ARG_VALUE synchronously on every platform,
guaranteeing the `watch:fs-watch-setup` catch arm runs. Restore the
strict assertions on phase + message.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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