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.

reaction_board/config.py

@@ -83,7 +83,8 @@ DEFAULT_CONFIG: dict[str, Any] = {
     "up_blacklist_seed": [],
     "schedule": {
         "discover_minutes": 60,
-        "snapshot_at": "00:01",
+        "snapshot_at": "23:15",
+        "seed_at": "00:01",
         "candidate_ttl_days": 7,
         "recent_snapshot_minutes": 60,
         "recent_video_days": 2,
@@ -179,6 +180,7 @@ class FolderConfig:
 class ScheduleConfig:
     discover_minutes: int
     snapshot_at: str
+    seed_at: str
     candidate_ttl_days: int
     recent_snapshot_minutes: int
     recent_video_days: int
@@ -449,14 +451,18 @@ def _build_config(data: Mapping[str, Any], path: Path) -> AppConfig:
     sched_raw = data["schedule"]
     if not isinstance(sched_raw, Mapping):
         raise ConfigError("schedule 必须是对象")
-    snapshot_at = _as_str(sched_raw.get("snapshot_at", "00:01"), "schedule.snapshot_at")
+    snapshot_at = _as_str(sched_raw.get("snapshot_at", "23:15"), "schedule.snapshot_at")
     if not _SNAPSHOT_AT_RE.match(snapshot_at):
         raise ConfigError("schedule.snapshot_at 必须是 HH:MM（24 小时制）")
+    seed_at = _as_str(sched_raw.get("seed_at", "00:01"), "schedule.seed_at")
+    if not _SNAPSHOT_AT_RE.match(seed_at):
+        raise ConfigError("schedule.seed_at 必须是 HH:MM（24 小时制）")
     schedule = ScheduleConfig(
         discover_minutes=_as_int(
             sched_raw.get("discover_minutes", 60), "schedule.discover_minutes", minimum=1
         ),
         snapshot_at=snapshot_at,
+        seed_at=seed_at,
         candidate_ttl_days=_as_int(
             sched_raw.get("candidate_ttl_days", 7),
             "schedule.candidate_ttl_days",