feat: EOD 23:15 seal + midnight seed shell for video/fans

Move daily snapshot/fans to 23:15 and add 00:01 seed that clones
last_completed ok=1 rows into today without advancing completed.
Evening runs force through seed markers; growth previous is per-aid
adjacent. Home shows short-update clock + 全站数据 date, and 收录视频
counts.

tests/test_config.py

@@ -154,7 +154,8 @@ def test_analytics_defaults_and_validation():
         }
         data["schedule"] = {
             "discover_minutes": 30,
-            "snapshot_at": "00:01",
+            "snapshot_at": "23:15",
+            "seed_at": "00:01",
             "candidate_ttl_days": 7,
             "recent_snapshot_minutes": 15,
             "recent_video_days": 3,
@@ -276,7 +277,8 @@ def test_schedule_recent_validation():
             data = base_config()
             data["schedule"] = {
                 "discover_minutes": 60,
-                "snapshot_at": "00:01",
+                "snapshot_at": "23:15",
+                "seed_at": "00:01",
                 "candidate_ttl_days": 7,
                 **bad,
             }