feat: Implement type casting for channel states and events, refine Shelly device online/offline logic, and improve event handling on server startup.

server.js

@@ -28,6 +28,14 @@ db.serialize(() => {
 
     // Events table - references channels
     db.run("CREATE TABLE IF NOT EXISTS events (id INTEGER PRIMARY KEY AUTOINCREMENT, channel_id INTEGER, event TEXT, timestamp TEXT, FOREIGN KEY(channel_id) REFERENCES channels(id))");
+
+    // Insert offline events for all online channels on startup (to prevent deduplication issues after restart)
+    db.run(`INSERT INTO events (channel_id, event, timestamp) 
+            SELECT c.id, 'false', datetime('now') 
+            FROM channels c 
+            WHERE c.field = 'online' 
+            AND EXISTS (SELECT 1 FROM events e WHERE e.channel_id = c.id AND e.event = 'true' 
+                        AND e.id = (SELECT MAX(e2.id) FROM events e2 WHERE e2.channel_id = c.id))`);
 });
 
 // Upstream Client Integration