Fix scheduler to read check interval from config each cycle

Previously the scheduler used the instance variable set at initialization,
ignoring config changes. Now it reads check_interval_hours from the config
database each cycle, allowing users to change the interval without restarting.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/update_scheduler.py

@@ -114,8 +114,9 @@ class UpdateScheduler:
 
         try:
             while not self._stop_event.is_set():
-                # Check if auto-update is enabled
+                # Read current config values (so changes take effect)
                 auto_enabled = self.store.get_config("auto_update_enabled", "false")
+                interval_hours = float(self.store.get_config("check_interval_hours", "24"))
 
                 if auto_enabled.lower() == "true":
                     # Run the check
@@ -124,13 +125,11 @@ class UpdateScheduler:
                     # Process any pending auto-updates
                     self._loop.run_until_complete(self._download_pending_updates())
 
-                # Calculate next check time
-                self._state.next_check = datetime.now() + timedelta(
-                    hours=self.check_interval_hours
-                )
+                # Calculate next check time using config value
+                self._state.next_check = datetime.now() + timedelta(hours=interval_hours)
 
                 # Wait for interval or stop signal
-                interval_seconds = self.check_interval_hours * 3600
+                interval_seconds = interval_hours * 3600
                 self._stop_event.wait(timeout=interval_seconds)
 
         finally: