feat(backend): remove browse-page cache, add Sentry/GlitchTip, rename MinIO buckets

- Remove BrowseStore interface + all browse MinIO ops (PutBrowsePage, GetBrowsePage,
  BrowseObjectKey, putBrowse, getBrowse); the /api/browse endpoint was replaced by
  the Meilisearch-backed /api/catalogue route
- Remove browse_refresh.go and the 6h browse refresh ticker in runner
- Add Sentry/GlitchTip error tracking to both backend and runner binaries via
  github.com/getsentry/sentry-go; opt-in via GLITCHTIP_DSN env var
- Wrap http.ServeMux with sentryhttp middleware for automatic panic recovery
- Rename MinIO bucket defaults: libnovel-chapters→chapters, libnovel-audio→audio,
  libnovel-browse→catalogue (env vars still override)
- Remove staged compiled binaries (backend/bin/runner, backend/healthcheck)

v3/backend/internal/config/config.go

@@ -145,10 +145,10 @@ func Load() Config {
 			SecretKey:      envOr("MINIO_SECRET_KEY", "changeme123"),
 			UseSSL:         envBool("MINIO_USE_SSL", false),
 			PublicUseSSL:   envBool("MINIO_PUBLIC_USE_SSL", true),
-			BucketChapters: envOr("MINIO_BUCKET_CHAPTERS", "libnovel-chapters"),
-			BucketAudio:    envOr("MINIO_BUCKET_AUDIO", "libnovel-audio"),
+			BucketChapters: envOr("MINIO_BUCKET_CHAPTERS", "chapters"),
+			BucketAudio:    envOr("MINIO_BUCKET_AUDIO", "audio"),
 			BucketAvatars:  envOr("MINIO_BUCKET_AVATARS", "avatars"),
-			BucketBrowse:   envOr("MINIO_BUCKET_BROWSE", "libnovel-browse"),
+			BucketBrowse:   envOr("MINIO_BUCKET_BROWSE", "catalogue"),
 		},
 
 		Kokoro: Kokoro{

v3/backend/internal/config/config_test.go

@@ -33,8 +33,8 @@ func TestLoad_Defaults(t *testing.T) {
 	if cfg.PocketBase.URL != "http://localhost:8090" {
 		t.Errorf("PocketBase.URL: want http://localhost:8090, got %q", cfg.PocketBase.URL)
 	}
-	if cfg.MinIO.BucketChapters != "libnovel-chapters" {
-		t.Errorf("MinIO.BucketChapters: want libnovel-chapters, got %q", cfg.MinIO.BucketChapters)
+	if cfg.MinIO.BucketChapters != "chapters" {
+		t.Errorf("MinIO.BucketChapters: want chapters, got %q", cfg.MinIO.BucketChapters)
 	}
 	if cfg.MinIO.UseSSL != false {
 		t.Errorf("MinIO.UseSSL: want false, got %v", cfg.MinIO.UseSSL)