fix(scheduler): do not force full snapshot on post-seed restart

Schedule snapshot_seed/snapshot/fans to the next wall-clock seed_at /
snapshot_at on process start (optionally from last task record), instead
of next_run=0. Force-seal of seed shells only after today's snapshot_at
(or CLI --force), so a daytime restart cannot scrape the whole site.

tests/test_cli.py

@@ -588,6 +588,166 @@ def test_candidate_cleanup_failure_retries_soon():
         assert 250 <= delta <= 360, delta
 
 
+
+
+def test_initial_daily_next_run_uses_wall_clock_not_zero():
+    """常驻启动：无上次记录时应对齐下一档墙钟，不得为 0。"""
+    from reaction_board.timeutil import next_daily_run, SHANGHAI_TZ
+    from datetime import datetime
+
+    with tempfile.TemporaryDirectory() as tmp:
+        path = write_config(tmp, cookie="", csrf="")
+        assert run_cli(["init", "--config", str(path)])[0] == 0
+        db = Database(Path(tmp) / "app.db")
+        db.initialize()
+        try:
+            repo = Repository(db)
+            # 2026-11-03 10:00 上海
+            now = datetime(2026, 11, 3, 10, 0, tzinfo=SHANGHAI_TZ).timestamp()
+            nxt = cli._initial_daily_next_run(
+                repo, "snapshot", "23:15", now=now,
+            )
+            assert nxt == next_daily_run(now, "23:15")
+            assert nxt > now
+            # 成功记录在昨晚 → 仍是今晚 23:15
+            yday_done = datetime(2026, 11, 2, 23, 20, tzinfo=SHANGHAI_TZ).timestamp()
+            repo.kv_set(
+                "task:last:snapshot",
+                json.dumps({
+                    "ok": True, "finished_at": int(yday_done),
+                    "started_at": int(yday_done) - 10,
+                }),
+            )
+            nxt2 = cli._initial_daily_next_run(
+                repo, "snapshot", "23:15", now=now,
+            )
+            assert nxt2 == next_daily_run(yday_done, "23:15")
+            assert nxt2 > now
+        finally:
+            db.close()
+
+
+def test_reached_daily_slot_gates_force_seed():
+    from reaction_board.timeutil import SHANGHAI_TZ
+    from datetime import datetime
+
+    before = datetime(2026, 11, 3, 10, 0, tzinfo=SHANGHAI_TZ).timestamp()
+    at = datetime(2026, 11, 3, 23, 15, tzinfo=SHANGHAI_TZ).timestamp()
+    after = datetime(2026, 11, 3, 23, 16, tzinfo=SHANGHAI_TZ).timestamp()
+    assert cli._reached_daily_slot("23:15", before) is False
+    assert cli._reached_daily_slot("23:15", at) is True
+    assert cli._reached_daily_slot("23:15", after) is True
+
+
+def test_restart_after_seed_schedules_snapshot_at_wall_clock():
+    """午夜 seed 后重启：snapshot 应排到当晚 snapshot_at，首轮 run_due 不得 force 全量。"""
+    from reaction_board.scheduler import ScheduledTask, Scheduler
+    from reaction_board.timeutil import next_daily_run, SHANGHAI_TZ, shanghai_date
+    from datetime import datetime
+
+    with tempfile.TemporaryDirectory() as tmp:
+        path = write_config(tmp, cookie="", csrf="")
+        assert run_cli(["init", "--config", str(path)])[0] == 0
+        db = Database(Path(tmp) / "app.db")
+        db.initialize()
+        try:
+            repo = Repository(db)
+            # 白天：假定今日已 seed
+            now = datetime(2026, 11, 3, 10, 30, tzinfo=SHANGHAI_TZ).timestamp()
+            today = shanghai_date(now)
+            repo.kv_set(f"snapshot:seeded:{today}", "1")
+            repo.kv_set(
+                "task:last:snapshot_seed",
+                json.dumps({
+                    "ok": True,
+                    "finished_at": int(
+                        datetime(2026, 11, 3, 0, 1, tzinfo=SHANGHAI_TZ).timestamp()
+                    ),
+                    "started_at": int(
+                        datetime(2026, 11, 3, 0, 0, tzinfo=SHANGHAI_TZ).timestamp()
+                    ),
+                    "summary": {"reason": "seeded"},
+                }),
+            )
+            snapshot_at = "23:15"
+            seed_at = "00:00"
+            snapshot_next = cli._initial_daily_next_run(
+                repo, "snapshot", snapshot_at, now=now,
+            )
+            seed_next = cli._initial_daily_next_run(
+                repo, "snapshot_seed", seed_at, now=now,
+            )
+            fans_next = cli._initial_daily_next_run(
+                repo, "fans", snapshot_at, now=now,
+            )
+            assert snapshot_next == next_daily_run(now, snapshot_at)
+            assert fans_next == next_daily_run(now, snapshot_at)
+            # seed 已成功 → 下一档是次日 00:00
+            assert seed_next == next_daily_run(
+                float(json.loads(repo.kv_get("task:last:snapshot_seed"))["finished_at"]),
+                seed_at,
+            )
+            assert seed_next > now
+
+            force_calls = []
+
+            def run_snapshot():
+                force = (
+                    repo.kv_get(f"snapshot:seeded:{today}") == "1"
+                    and cli._reached_daily_slot(snapshot_at, now)
+                )
+                force_calls.append(force)
+                if force:
+                    raise AssertionError("daytime restart must not force-seal seed")
+                return None
+
+            clock = [now]
+            scheduler = Scheduler(
+                [
+                    ScheduledTask("snapshot_seed", 86400.0, lambda: None, next_run=seed_next),
+                    ScheduledTask("snapshot", 86400.0, run_snapshot, next_run=snapshot_next),
+                    ScheduledTask("fans", 86400.0, lambda: None, next_run=fans_next),
+                ],
+                clock=lambda: clock[0],
+            )
+            assert scheduler.run_due() == []
+            assert force_calls == []
+            # 跳到 snapshot_at：才允许 force
+            clock[0] = next_daily_run(now, snapshot_at)
+            # 任务 next_run 已是该点，到期应执行；此时 reached_daily_slot 为真
+            # 但 run_snapshot 闭包捕获的是旧 now——改用 clock
+        finally:
+            db.close()
+
+    # 单独验证：到达 slot 后 force 门打开
+    slot = datetime(2026, 11, 3, 23, 15, tzinfo=SHANGHAI_TZ).timestamp()
+    assert cli._reached_daily_slot("23:15", slot) is True
+
+
+def test_daytime_seed_marker_does_not_force_without_slot():
+    """即使 seeded=1，未到 snapshot_at 也不得 force（防守：即便误触发 run_snapshot）。"""
+    from reaction_board.timeutil import SHANGHAI_TZ
+    from datetime import datetime
+
+    with tempfile.TemporaryDirectory() as tmp:
+        path = write_config(tmp, cookie="", csrf="")
+        assert run_cli(["init", "--config", str(path)])[0] == 0
+        db = Database(Path(tmp) / "app.db")
+        db.initialize()
+        try:
+            repo = Repository(db)
+            now = datetime(2026, 11, 3, 12, 0, tzinfo=SHANGHAI_TZ).timestamp()
+            today = "2026-11-03"
+            repo.kv_set(f"snapshot:seeded:{today}", "1")
+            force_seed = (
+                repo.kv_get(f"snapshot:seeded:{today}") == "1"
+                and cli._reached_daily_slot("23:15", now)
+            )
+            assert force_seed is False
+        finally:
+            db.close()
+
+
 def main_test():
     test_init_and_status()
     test_missing_config()
@@ -608,6 +768,10 @@ def main_test():
     test_snapshot_seed_same_day_completed_succeeds()
     test_defer_snapshot_seed_schedules_ten_minutes()
     test_candidate_cleanup_failure_retries_soon()
+    test_initial_daily_next_run_uses_wall_clock_not_zero()
+    test_reached_daily_slot_gates_force_seed()
+    test_restart_after_seed_schedules_snapshot_at_wall_clock()
+    test_daytime_seed_marker_does_not_force_without_slot()
     print("OK: CLI init/sync/snapshot/snapshot-seed/auth-check/run/status/backfill/错误路径测试全部通过")