feat: add dev mode with DEV_ env prefix

Support dual configuration: PROXY_TOKEN/SERVER_URL for production,
DEV_PROXY_TOKEN/DEV_SERVER_URL for local development.

- npm start → production
- npm run start:dev → dev (PROXY_MODE=dev)
- npm run dev → dev with hot-reload
- Restore PTY auto-creation on sync_state for existing chats

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/main.ts

@@ -23,15 +23,16 @@ import { existsSync, readdirSync, statSync, readFileSync } from 'fs';
 class ClaudeCliProxy {
   private ws: WsClient;
   private pty: PtyManager;
+  private config: ReturnType<typeof loadConfig>;
 
   constructor() {
-    const config = loadConfig();
+    this.config = loadConfig();
 
     this.pty = new PtyManager();
 
     this.ws = new WsClient({
-      url: config.serverUrl,
-      token: config.proxyToken,
+      url: this.config.serverUrl,
+      token: this.config.proxyToken,
       onMessage: (msg) => this.handleMessage(msg),
       onBinary: (data) => this.handleBinaryFrame(data),
       onConnected: () => this.onConnected(),
@@ -40,7 +41,8 @@ class ClaudeCliProxy {
   }
 
   async start(): Promise<void> {
-    console.log('[proxy] Starting claude-cli-proxy (xterm mode)...');
+    const mode = this.config.isDev ? 'DEV' : 'PROD';
+    console.log(`[proxy] Starting claude-cli-proxy (${mode}) → ${this.config.serverUrl}`);
 
     this.ws.connect();
 
@@ -114,15 +116,23 @@ class ClaudeCliProxy {
     const activePtys = new Set(this.pty.listPtys());
     const chatIds = new Set(payload.chats.map((c) => c.id));
 
-    // Only send replay + pty_ready for PTYs that already exist
-    // Do NOT auto-create PTYs — they should only be created via explicit create_pty
     for (const chat of payload.chats) {
       if (activePtys.has(chat.id)) {
+        // PTY exists — send replay + ready
         const replay = this.pty.getReplayBuffer(chat.id);
         if (replay) {
           this.ws.sendBinary(encodeBinaryFrame(DIR_PTY_OUTPUT, chat.id, replay));
         }
         this.ws.send({ type: 'pty_ready', payload: { chatId: chat.id } });
+      } else if (chat.workDir) {
+        // PTY not running — create it
+        this.handleCreatePty({
+          chatId: chat.id,
+          dir: chat.workDir,
+          resumeSessionId: chat.sessionId ?? undefined,
+          cols: chat.cols ?? 120,
+          rows: chat.rows ?? 40,
+        });
       }
     }