Show download date and watch status on Admin rows

Surfaces the download-age cutoff data (already computed for the 6-month
filter) directly on each row, plus an explicit "Never watched" label, so
the never-watched call behind the delete button is visible rather than
just trusted.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LPJxtE9tPURsaWDZ6rC4Dt

app.py

@@ -846,6 +846,7 @@ def get_admin_unwatched_shows(limit=10, months=ADMIN_UNWATCHED_MONTHS):
             "year": s.get("year", ""),
             "size": size,
             "ep_count": stats.get("episodeFileCount", 0),
+            "added": added,
         })
 
     never.sort(key=lambda x: x["size"], reverse=True)