Adds `messages` config option to session-memory hook (default: 15).
Fixes filter order bug - now filters user/assistant messages first,
then slices to get exactly N messages. Previously sliced first which
could result in fewer messages when non-message entries were present.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
The session-memory hook saves session context to memory files when /new is run,
which is useful internal housekeeping. However, the confirmation message that
was displayed to users (showing the file path) leaked implementation details.
This change removes the user-visible message while keeping the console.log
for debugging purposes. The hook continues to save session context silently.
