feat(admin): all-podcasts view — disk-first maintenance for every feed

§0 item 8 (Phase-4 item 1 pulled forward, user directive: maintenance
tooling ships WITH the features it maintains):

- /admin/podcasts (AdminMiddleware): every feed from EVERY user via the
  RLS admin escape (first-admin identity, poller/fetcher contract) —
  feed + host, library, subscriber count/names, downloaded/total, DISK
  USAGE, last fetch. Sorted disk DESC ('what's eating the disk'),
  totals header (feeds · episodes · bytes on disk).
- Per-feed actions: Refresh · Delete files (rows → pending, disk freed;
  confirms spell out the re-materialization contract) · Remove feed
  (rows + files for everyone — the same admin delete as the detail
  page). All confirms ride the global confirm modal.
- New sqlc: ListAllPodcastFeedsAdmin (correlated aggregates),
  ResetPodcastEpisodeFileDeleted / ResetPodcastFeedFilesDeleted —
  downloaded rows reset to pending with download-derived facts cleared
  (audio_metadata, chapter_count, cover, size, mime); file_path KEPT
  (fetch-maintained layout — a re-download lands on the same path).
  file deletion via the existing DeleteFeedFiles file-removal pattern
  (episode files + .cover.jpg siblings).
- Poll upsert never touches download_state, so deleted files STAY
  deleted — a feed refresh re-lists metadata but re-materializes
  nothing (pinned by TestAdminDeleteEpisodeFiles).
- Per-episode admin delete-file: POST /feeds/:id/episodes/:eid/
  delete-file (admin) — one episode's file gone, row pending, siblings
  untouched; HX swaps the episode list. (Found while testing: the
  handler first read c.Param("id") — the FEED's uuid — instead of
  :eid; the 404 'episode not found' trail led straight to it.)
- Tests: admin sees other users' feeds + subscriber names; regular
  users 403 on page AND actions; single + feed-level deletion reset
  rows/clear facts/delete files; refresh leaves pending rows pending.
- Admin nav gains 'Podcasts' under Administration.

Wrong-gotcha note for future agents: parseUUID on c.Param('id') inside
a /feeds/:id/episodes/:eid route resolves the FEED, not the episode.

internal/router/frontend.go

@@ -14,6 +14,7 @@ import (
 
 	"bookhoard/internal/config"
 	"bookhoard/internal/database"
+	"bookhoard/internal/rls"
 	"bookhoard/internal/handlers"
 	"bookhoard/internal/services"
 	"bookhoard/internal/utils"
@@ -1507,8 +1508,7 @@ func registerFrontendRoutes(cfg *Config) {
 
 	// Admin hash conflicts page: content-duplicate groups flagged during hash
 	// backfill or rescan, resolved by keeping all copies or merging into one.
-	frontendProtected.GET("/admin/hash-conflicts", handlers.AdminMiddleware(func(c *echo.Context) error {
-		user, err := getTemplateUserWithTheme(c, cfg)
+	frontendProtected.GET("/admin/hash-conflicts", handlers.AdminMiddleware(func(c *echo.Context) error {		user, err := getTemplateUserWithTheme(c, cfg)
 		if err != nil {
 			return renderErrorPage(c, "Error loading user", "user_load_error")
 		}
@@ -1562,6 +1562,62 @@ func registerFrontendRoutes(cfg *Config) {
 		return c.HTML(http.StatusOK, buf.String())
 	}))
 
+	// Admin all-podcasts view (§0 item 8): every feed from every user with
+	// maintenance aggregates (disk usage first). The aggregate read runs
+	// under the FIRST-ADMIN identity — the RLS admin escape (invariant
+	// 12, poller/fetcher contract) — so admins see feeds from libraries
+	// hidden even from them.
+	frontendProtected.GET("/admin/podcasts", handlers.AdminMiddleware(func(c *echo.Context) error {
+		user, err := getTemplateUserWithTheme(c, cfg)
+		if err != nil {
+			return renderErrorPage(c, "Error loading user", "user_load_error")
+		}
+
+		adminUUID, err := cfg.Queries.GetFirstAdmin(context.Background())
+		if err != nil {
+			return renderErrorPage(c, "Error loading podcasts", "podcasts_load_error")
+		}
+		// cfg.Queries is ScopedDB-backed: the context identity is all the
+		// aggregate read needs.
+		actx := rls.WithUser(c.Request().Context(), adminUUID)
+
+		rows, err := cfg.Queries.ListAllPodcastFeedsAdmin(actx)
+		if err != nil {
+			return renderErrorPage(c, "Error loading podcasts", "podcasts_load_error")
+		}
+
+		feeds := make([]templates.AdminPodcastFeedData, 0, len(rows))
+		var totalBytes int64
+		totalDownloaded, totalEpisodes := 0, 0
+		for _, r := range rows {
+			lastFetch := "never"
+			if r.LastFetchedAt.Valid {
+				lastFetch = r.LastFetchedAt.Time.In(utils.UserLocation(user.Timezone)).Format("Jan 2, 2006 15:04")
+			}
+			feeds = append(feeds, templates.AdminPodcastFeedData{
+				ID:                uuid.UUID(r.ID.Bytes).String(),
+				Title:             r.Title,
+				Host:              r.Host.String,
+				LibraryName:       r.LibraryName,
+				Subscribers:       int(r.SubscriberCount),
+				SubscriberNames:   r.SubscriberNames,
+				EpisodeTotal:      int(r.EpisodeTotal),
+				EpisodeDownloaded: int(r.EpisodeDownloaded),
+				DiskBytes:         r.DiskBytes,
+				LastFetched:       lastFetch,
+			})
+			totalBytes += r.DiskBytes
+			totalEpisodes += int(r.EpisodeTotal)
+			totalDownloaded += int(r.EpisodeDownloaded)
+		}
+
+		var buf bytes.Buffer
+		if err := templates.AdminPodcasts(user, feeds, len(feeds), totalDownloaded, totalEpisodes, totalBytes).Render(c.Request().Context(), &buf); err != nil {
+			return err
+		}
+		return c.HTML(http.StatusOK, buf.String())
+	}))
+
 	// Admin users page
 	frontendProtected.GET("/admin/users", handlers.AdminMiddleware(func(c *echo.Context) error {
 		user, err := getTemplateUserWithTheme(c, cfg)