fix(vibe): let a dislike outlive the session that heard it

Disliking a track in a Vibe wrote one row to the session ledger and
nothing else. The ledger only excludes a track from the session it was
recorded in, so the same track came back the next evening, and the one
after that. A dislike in a Vibe is the same verdict as a dislike
anywhere else, so it now takes the same path.

Two more things undid a dislike that did land. The library scan rewrote
every track's state from the file on disk, which restored every HIDDEN
track to LIBRARY on every scan; finding a file again says nothing about
whether the listener wants to hear it. And hiding only matched tracks in
LIBRARY, so a disliked probation recommendation stayed eligible.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KENqSChfyqWnor6ud2WWH6

backend/src/services/vibe-session-coordinator.service.ts

@@ -229,6 +229,14 @@ export class VibeSessionCoordinator {
       // guard for old coordinator test doubles during the migration.
       const projectSessionFeedback = (this.db as Partial<DbService>).projectVibeSessionFeedback;
       if (projectSessionFeedback) await projectSessionFeedback.call(this.db, result.event);
+      // A dislike in a Vibe is the same verdict as a dislike anywhere else. The
+      // ledger alone only excludes the track from this one session, which is
+      // why a disliked track kept coming back the next evening. Run it once per
+      // distinct event so a retried delivery cannot log a second feedback row.
+      if (input.type === 'disliked' && input.trackId && result.inserted) {
+        const dislikeTrack = (this.db as Partial<DbService>).dislikeTrack;
+        if (dislikeTrack) await dislikeTrack.call(this.db, userId, input.trackId);
+      }
       if (!isMaterialFeedback(input.type)) {
         const response = await this.getPlan(userId, sessionId);
         return { ...response, event: result.event, idempotent: !result.inserted };