feat(server/m7-353): admin endpoints for cover refetch (per-album + bulk)

Adds POST /api/admin/albums/{id}/cover/refetch (synchronous single-album
retry) and POST /api/admin/covers/refetch-missing (async bulk drain).
Wires coverart.Enricher through server.New → api.Mount → handlers struct.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/api/api.go

@@ -13,6 +13,7 @@ import (
 
 	"git.fabledsword.com/bvandeusen/minstrel/internal/auth"
 	"git.fabledsword.com/bvandeusen/minstrel/internal/config"
+	"git.fabledsword.com/bvandeusen/minstrel/internal/coverart"
 	"git.fabledsword.com/bvandeusen/minstrel/internal/lidarrconfig"
 	"git.fabledsword.com/bvandeusen/minstrel/internal/lidarrquarantine"
 	"git.fabledsword.com/bvandeusen/minstrel/internal/lidarrrequests"
@@ -24,17 +25,19 @@ import (
 // Mount attaches /api/* handlers to r. Public endpoints (login) are outside
 // RequireUser; everything else is gated by the middleware. The events writer
 // is shared with the Subsonic mount so /rest/scrobble feeds the same store.
-func Mount(r chi.Router, pool *pgxpool.Pool, logger *slog.Logger, events *playevents.Writer, recCfg config.RecommendationConfig, lidarrCfg *lidarrconfig.Service, lidarrReqs *lidarrrequests.Service, lidarrQuar *lidarrquarantine.Service, tracksSvc *tracks.Service, playlistsSvc *playlists.Service, dataDir string) {
+func Mount(r chi.Router, pool *pgxpool.Pool, logger *slog.Logger, events *playevents.Writer, recCfg config.RecommendationConfig, lidarrCfg *lidarrconfig.Service, lidarrReqs *lidarrrequests.Service, lidarrQuar *lidarrquarantine.Service, tracksSvc *tracks.Service, playlistsSvc *playlists.Service, coverEnricher *coverart.Enricher, coverBackfillCap int, dataDir string) {
 	rng := rand.New(rand.NewSource(rand.Int63()))
 	h := &handlers{
 		pool: pool, logger: logger, events: events, recCfg: recCfg,
-		rng:              rng.Float64,
-		lidarrCfg:        lidarrCfg,
-		lidarrRequests:   lidarrReqs,
-		lidarrQuarantine: lidarrQuar,
-		tracks:           tracksSvc,
-		playlists:        playlistsSvc,
-		dataDir:          dataDir,
+		rng:                rng.Float64,
+		lidarrCfg:          lidarrCfg,
+		lidarrRequests:     lidarrReqs,
+		lidarrQuarantine:   lidarrQuar,
+		tracks:             tracksSvc,
+		playlists:          playlistsSvc,
+		coverart:           coverEnricher,
+		coverArtBackfillCap: coverBackfillCap,
+		dataDir:            dataDir,
 	}
 
 	r.Route("/api", func(api chi.Router) {
@@ -101,6 +104,9 @@ func Mount(r chi.Router, pool *pgxpool.Pool, logger *slog.Logger, events *playev
 				admin.Get("/quarantine/actions", h.handleListQuarantineActions)
 
 				admin.Delete("/tracks/{id}", h.handleRemoveTrack)
+
+				admin.Post("/albums/{id}/cover/refetch", h.handleAdminAlbumRefetchCover)
+				admin.Post("/covers/refetch-missing", h.handleAdminBulkRefetchCovers)
 			})
 
 			authed.Get("/playlists", h.handleListPlaylists)
@@ -117,15 +123,17 @@ func Mount(r chi.Router, pool *pgxpool.Pool, logger *slog.Logger, events *playev
 }
 
 type handlers struct {
-	pool             *pgxpool.Pool
-	logger           *slog.Logger
-	events           *playevents.Writer
-	recCfg           config.RecommendationConfig
-	rng              func() float64
-	lidarrCfg        *lidarrconfig.Service
-	lidarrRequests   *lidarrrequests.Service
-	lidarrQuarantine *lidarrquarantine.Service
-	tracks           *tracks.Service
-	playlists        *playlists.Service
-	dataDir          string
+	pool                *pgxpool.Pool
+	logger              *slog.Logger
+	events              *playevents.Writer
+	recCfg              config.RecommendationConfig
+	rng                 func() float64
+	lidarrCfg           *lidarrconfig.Service
+	lidarrRequests      *lidarrrequests.Service
+	lidarrQuarantine    *lidarrquarantine.Service
+	tracks              *tracks.Service
+	playlists           *playlists.Service
+	coverart            *coverart.Enricher
+	coverArtBackfillCap int
+	dataDir             string
 }