gsd-check-update.js looked for hooks in configDir/hooks/ (e.g.,
~/.claude/hooks/) but the installer writes hooks to
configDir/get-shit-done/hooks/. This mismatch caused false stale
hook warnings that persisted even after updating.
Also clears the update cache during install so the next session
re-evaluates hook versions with the correct path.
Closes#1249
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>