Dashboard detail, library filtering/pagination, simplified playlist times,

job descriptions

Dashboard: format breakdown (FLAC/MP3/etc. counts), approximate library
size (bitrate*length/8, same approximation `beet stats` itself uses --
verified to match its "100.5 GiB" output exactly against the real
library), and a credential auth-state summary per scope (configured y/n
plus, for Bandcamp, cookie expiry parsed locally from the stored cookie
jar -- deliberately not a live network probe like pipeline-status.sh's
Qobuz check, since this renders on every dashboard load).

Library: was one unfiltered page dumping all 4072 tracks. Added search
(artist/title/album), playlist and format filter dropdowns, and real
SQL-level pagination (LIMIT/OFFSET, not fetch-everything-then-slice).
beets_service gained count_items()/distinct_formats() to support this.

Playlists: cron_expr is still the stored/scheduled representation, but the
UI now shows and edits a plain daily time picker instead of raw cron
syntax -- every playlist schedule today is a simple daily HH:MM anyway.
playlist_service.cron_to_time()/time_to_cron() convert at the router
boundary; verified round-trip against all real playlist cron values.

Jobs: each maintenance job now shows a short one-line description of what
it actually does (MAINTENANCE_JOB_DESCRIPTIONS), and "next run" is
formatted consistently with playlists' time style (HH:MM, with a day
qualifier for non-today runs -- maintenance jobs can be weekly/monthly,
unlike playlists' plain daily schedule).

Verified end-to-end against the real production data (4072 tracks, 100.5
GiB, real credentials): stats/format-breakdown/search/pagination all
correct, all 7 credential scopes report configured with Bandcamp's real
cookie expiry (325 days), and a full authenticated page-render sweep
(dashboard, library with every filter combination, playlist detail,
jobs) all returned 200 with no template errors.

app/routers/playlists.py

@@ -13,20 +13,27 @@ templates = Jinja2Templates(directory="app/templates")
 @router.get("")
 async def playlists_index(request: Request, user: dict = Depends(require_auth), db=Depends(get_db)):
     playlists = playlist_service.list_all(db)
-    return templates.TemplateResponse(request, "playlists/index.html", {"playlists": playlists})
+    sync_times = {p.id: playlist_service.cron_to_time(p.cron_expr) for p in playlists}
+    return templates.TemplateResponse(
+        request, "playlists/index.html", {"playlists": playlists, "sync_times": sync_times}
+    )
 
 
 @router.post("")
 async def create_playlist(
     name: str = Form(...),
     spotify_url: str = Form(...),
-    cron_expr: str = Form(""),
+    sync_time: str = Form(""),
     no_m3u: bool = Form(False),
     user: dict = Depends(require_auth),
     db=Depends(get_db),
 ):
     playlist_service.create(
-        db, name=name, spotify_url=spotify_url, cron_expr=cron_expr or None, no_m3u=no_m3u
+        db,
+        name=name,
+        spotify_url=spotify_url,
+        cron_expr=playlist_service.time_to_cron(sync_time),
+        no_m3u=no_m3u,
     )
     return RedirectResponse(url="/playlists", status_code=303)
 
@@ -49,7 +56,12 @@ async def playlist_detail(
     return templates.TemplateResponse(
         request,
         "playlists/detail.html",
-        {"playlist": playlist, "status": status, "error": error},
+        {
+            "playlist": playlist,
+            "sync_time": playlist_service.cron_to_time(playlist.cron_expr),
+            "status": status,
+            "error": error,
+        },
     )
 
 
@@ -57,7 +69,7 @@ async def playlist_detail(
 async def update_playlist(
     playlist_id: int,
     active: bool = Form(False),
-    cron_expr: str = Form(""),
+    sync_time: str = Form(""),
     no_m3u: bool = Form(False),
     notes: str = Form(""),
     user: dict = Depends(require_auth),
@@ -67,7 +79,7 @@ async def update_playlist(
         db,
         playlist_id,
         active=active,
-        cron_expr=cron_expr or None,
+        cron_expr=playlist_service.time_to_cron(sync_time),
         no_m3u=no_m3u,
         notes=notes or None,
     )