feat: remind from due Week Ahead plans (Closes #1192)

tests/test_start_day_reminders.py

@@ -281,15 +281,18 @@ async def test_authenticated_device_can_enable_start_day_reminders(tmp_path, mon
 
 
 @pytest.mark.anyio
-async def test_worker_snapshot_reads_the_confirmed_accounts_tomorrow_plan(monkeypatch):
+async def test_worker_snapshot_reads_the_confirmed_accounts_next_planned_day(monkeypatch):
     async def current_user():
         return {"login": "Timmy"}
 
     class Store:
-        def get_tomorrow(self, login):
+        def get_start_day_plan(self, login):
             assert login == "Timmy"
             return {"ids": ["one"], "plan_date": "2026-08-20"}
 
+        def get_tomorrow(self, _login):
+            raise AssertionError("the worker must use Week Ahead discovery")
+
     monkeypatch.setattr(main, "current_user", current_user)
     monkeypatch.setattr(main, "_today_store", lambda: Store())
 

tests/test_week_plan.py

@@ -51,6 +51,72 @@ def test_week_plan_is_encrypted_account_scoped_revisioned_and_preserves_other_da
     assert conflict.value.snapshot == updated
 
 
+def test_start_day_plan_selects_earliest_nonempty_week_date_without_mutation(tmp_path):
+    store = TodayStore(
+        tmp_path / "today.sqlite3", encryption_key=b"r" * 32,
+        clock=lambda: datetime(2026, 8, 21, 13, tzinfo=timezone.utc).timestamp(),
+    )
+    days = [
+        {
+            "plan_date": "2026-08-20", "ids": [],
+            "capacity_minutes": 60, "estimates": {},
+        },
+        {
+            "plan_date": "2026-08-21", "ids": ["issue:private/repo:7:"],
+            "capacity_minutes": 90,
+            "estimates": {"issue:private/repo:7:": 45},
+        },
+        {
+            "plan_date": "2026-08-22", "ids": ["issue:private/repo:8:"],
+            "capacity_minutes": 120,
+            "estimates": {"issue:private/repo:8:": 30},
+        },
+    ]
+    week = store.replace_week(
+        "timmy", base_revision=0, days=days, timezone="America/New_York"
+    )
+
+    assert store.get_start_day_plan("Timmy") == {
+        **days[1], "timezone": "America/New_York",
+    }
+    assert store.get_week("timmy") == week
+
+
+def test_start_day_plan_falls_back_to_tomorrow_without_migrating_it(tmp_path):
+    store = TodayStore(tmp_path / "today.sqlite3", encryption_key=b"r" * 32)
+    tomorrow = store.replace_tomorrow(
+        "timmy", base_revision=0, ids=["issue:private/repo:9:"],
+        capacity_minutes=75, estimates={"issue:private/repo:9:": 45},
+        plan_date="2026-08-21", timezone="UTC",
+    )
+
+    assert store.get_start_day_plan("timmy") == tomorrow
+    assert store.get_tomorrow("timmy") == tomorrow
+    with store._connect() as connection:
+        assert connection.execute(
+            "SELECT COUNT(*) FROM week_plans WHERE login = ?", ("timmy",)
+        ).fetchone()[0] == 0
+
+
+def test_start_day_plan_uses_due_tomorrow_fallback_before_future_week_day(tmp_path):
+    store = TodayStore(
+        tmp_path / "today.sqlite3", encryption_key=b"r" * 32,
+        clock=lambda: datetime(2026, 8, 20, 13, tzinfo=timezone.utc).timestamp(),
+    )
+    future = [{
+        "plan_date": "2026-08-21", "ids": ["issue:private/repo:10:"],
+        "capacity_minutes": 90, "estimates": {"issue:private/repo:10:": 45},
+    }]
+    store.replace_week("timmy", base_revision=0, days=future, timezone="UTC")
+    tomorrow = store.replace_tomorrow(
+        "timmy", base_revision=0, ids=["issue:private/repo:9:"],
+        capacity_minutes=75, estimates={"issue:private/repo:9:": 45},
+        plan_date="2026-08-20", timezone="UTC",
+    )
+
+    assert store.get_start_day_plan("timmy") == tomorrow
+
+
 def test_week_plan_rejects_the_same_work_on_multiple_dates_without_advancing_revision(tmp_path):
     store = TodayStore(tmp_path / "today.sqlite3", encryption_key=b"w" * 32)
     original = store.replace_week(