Enhance README and RPC for package management

- Added instructions to README.md for building an ISO from source and flashing it to USB.
- Introduced a new RPC method for package installation, including security checks and container management.
- Updated Docker and Podman integration in build scripts to support both container runtimes.
- Enhanced Nginx configuration for improved timeout settings and WebSocket support.
- Added new app metadata for additional applications in the Docker package scanner.

neode-ui/src/api/websocket.ts

@@ -18,6 +18,9 @@ export class WebSocketClient {
   private reconnectTimer: ReturnType<typeof setTimeout> | null = null
   private visibilityChangeHandler: (() => void) | null = null
   private onlineHandler: (() => void) | null = null
+  private heartbeatTimer: ReturnType<typeof setTimeout> | null = null
+  private lastMessageTime: number = Date.now()
+  private heartbeatInterval = 10000 // Check connection every 10 seconds
 
   constructor(url: string = '/ws/db') {
     this.url = url
@@ -132,8 +135,10 @@ export class WebSocketClient {
       this.ws.onopen = () => {
         clearTimeout(connectionTimeout)
         this.reconnectAttempts = 0
+        this.lastMessageTime = Date.now()
         console.log('[WebSocket] Connected successfully')
         this.notifyConnectionState(true)
+        this.startHeartbeat()
         resolve()
       }
 
@@ -145,6 +150,7 @@ export class WebSocketClient {
       }
 
       this.ws.onmessage = (event) => {
+        this.lastMessageTime = Date.now()
         try {
           const update: Update = JSON.parse(event.data)
           this.callbacks.forEach((callback) => callback(update))
@@ -155,6 +161,7 @@ export class WebSocketClient {
 
       this.ws.onclose = (event) => {
         clearTimeout(connectionTimeout)
+        this.stopHeartbeat()
         console.log('[WebSocket] Closed', { code: event.code, reason: event.reason, wasClean: event.wasClean })
         
         // Notify connection state changed
@@ -243,9 +250,39 @@ export class WebSocketClient {
     this.connectionStateCallbacks.forEach((callback) => callback(connected))
   }
 
+  private startHeartbeat(): void {
+    this.stopHeartbeat()
+    
+    this.heartbeatTimer = setInterval(() => {
+      if (!this.ws || this.ws.readyState !== WebSocket.OPEN) {
+        console.warn('[WebSocket] Heartbeat detected closed connection')
+        this.stopHeartbeat()
+        return
+      }
+      
+      // Check if we've received a message recently
+      const timeSinceLastMessage = Date.now() - this.lastMessageTime
+      
+      // If no message for more than 60 seconds, assume connection is stale
+      if (timeSinceLastMessage > 60000) {
+        console.warn('[WebSocket] No messages for 60s, reconnecting...')
+        this.ws.close()
+        return
+      }
+    }, this.heartbeatInterval)
+  }
+
+  private stopHeartbeat(): void {
+    if (this.heartbeatTimer) {
+      clearInterval(this.heartbeatTimer)
+      this.heartbeatTimer = null
+    }
+  }
+
   disconnect(): void {
     this.shouldReconnect = false
     this.reconnectAttempts = 0
+    this.stopHeartbeat()
     
     // Clear reconnect timer
     if (this.reconnectTimer) {