fix(scheduler): honor app timezone for cron triggers and log scheduled events

CronTrigger.from_crontab was constructed without a timezone, so a cron like
'0 9 * * *' fired at 09:00 host-local instead of 09:00 in the admin-configured
timezone. Now all tracker/action cron triggers are built with the app tz, and
the setting endpoint rebuilds existing cron jobs when the tz changes (since
CronTrigger freezes its tz at construction time).

The scheduler provider also renders current_date/time/datetime/weekday in the
configured tz and exposes a new 'timezone' template variable.

EventLog entries for scheduled_message now include schedule_type,
cron_expression/interval_seconds, timezone, and fire_count, and the dashboard
shows the event type with a label/icon/color.

packages/core/src/notify_bridge_core/providers/scheduler/provider.py

@@ -5,6 +5,7 @@ from __future__ import annotations
 import logging
 from datetime import datetime, timezone
 from typing import Any
+from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
 from notify_bridge_core.models.events import EventType, ServiceEvent
 from notify_bridge_core.providers.base import ServiceProvider, ServiceProviderType
@@ -57,6 +58,13 @@ SCHEDULER_VARIABLES: list[TemplateVariableDefinition] = [
         example="Monday",
         provider_type=ServiceProviderType.SCHEDULER,
     ),
+    TemplateVariableDefinition(
+        name="timezone",
+        type="string",
+        description="IANA timezone used to compute current_date/time",
+        example="Europe/Warsaw",
+        provider_type=ServiceProviderType.SCHEDULER,
+    ),
     TemplateVariableDefinition(
         name="custom_vars",
         type="dict",
@@ -83,7 +91,8 @@ class SchedulerServiceProvider(ServiceProvider):
         custom_variables: dict[str, str] | None = None,
         date_format: str = "%d.%m.%Y",
         time_format: str = "%H:%M",
-        datetime_format: str = "%d.%m.%Y, %H:%M UTC",
+        datetime_format: str = "%d.%m.%Y, %H:%M %Z",
+        timezone_name: str | None = None,
     ) -> None:
         self._name = name
         self._tracker_name = tracker_name
@@ -91,6 +100,18 @@ class SchedulerServiceProvider(ServiceProvider):
         self._date_format = date_format
         self._time_format = time_format
         self._datetime_format = datetime_format
+        # Resolve a timezone for date/time rendering. Falls back to UTC on
+        # invalid IANA names so a typo in app settings doesn't break polls.
+        tz: ZoneInfo
+        if timezone_name:
+            try:
+                tz = ZoneInfo(timezone_name)
+            except (ZoneInfoNotFoundError, ValueError):
+                _LOGGER.warning("Unknown timezone %r; falling back to UTC", timezone_name)
+                tz = ZoneInfo("UTC")
+        else:
+            tz = ZoneInfo("UTC")
+        self._tz = tz
 
     async def connect(self) -> bool:
         return True  # virtual provider — always connected
@@ -103,7 +124,8 @@ class SchedulerServiceProvider(ServiceProvider):
         collection_ids: list[str],
         tracker_state: dict[str, Any],
     ) -> tuple[list[ServiceEvent], dict[str, Any]]:
-        now = datetime.now(timezone.utc)
+        now_utc = datetime.now(timezone.utc)
+        now = now_utc.astimezone(self._tz)
         # State uses {collection_id: {dict}} convention like other providers
         sched_state = tracker_state.get("scheduler", {})
         fire_count = sched_state.get("fire_count", 0) + 1
@@ -115,6 +137,7 @@ class SchedulerServiceProvider(ServiceProvider):
             "current_time": now.strftime(self._time_format),
             "current_datetime": now.strftime(self._datetime_format),
             "weekday": _WEEKDAYS[now.weekday()],
+            "timezone": self._tz.key,
             "custom_vars": dict(self._custom_variables),
         }
         # Flatten custom variables at top level for easy template access

packages/core/src/notify_bridge_core/templates/context.py

@@ -224,6 +224,7 @@ def build_template_context(
         ctx.setdefault("current_time", event.extra.get("current_time", ""))
         ctx.setdefault("current_datetime", event.extra.get("current_datetime", ""))
         ctx.setdefault("weekday", event.extra.get("weekday", ""))
+        ctx.setdefault("timezone", event.extra.get("timezone", "UTC"))
         ctx.setdefault("custom_vars", event.extra.get("custom_vars", {}))
 
     return ctx