feat: Integrate Electric SQL for real-time notifications and enhance PostgreSQL configuration

- Added Electric SQL service to docker-compose for real-time data synchronization.
- Introduced PostgreSQL configuration for logical replication and performance tuning.
- Created scripts for initializing Electric SQL user and electrifying tables.
- Implemented notification model and service in the backend.
- Developed ElectricProvider and useNotifications hook in the frontend for managing notifications.
- Updated environment variables and package dependencies for Electric SQL integration.

surfsense_web/lib/electric/auth.ts

@@ -0,0 +1,21 @@
+/**
+ * Get auth token for Electric SQL
+ * In production, this should get the token from your auth system
+ */
+
+export async function getElectricAuthToken(): Promise<string> {
+	// For insecure mode (development), return empty string
+	if (process.env.NEXT_PUBLIC_ELECTRIC_AUTH_MODE === 'insecure') {
+		return ''
+	}
+
+	// In production, get token from your auth system
+	// This should match your backend auth token
+	if (typeof window !== 'undefined') {
+		const token = localStorage.getItem('surfsense_bearer_token')
+		return token || ''
+	}
+
+	return ''
+}
+