fix: emit needsRefresh after OpenCode TUI stabilizes

After the 3s TUI stabilization timeout, emit needsRefresh so the
client fetches the full terminal buffer. Without this, the terminal
appears empty until the user manually refreshes or switches tabs.

Wire needsRefresh as a proper session listener in server.ts with
cleanup in both removal paths to prevent memory leaks.

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

src/web/server.ts

@@ -307,6 +307,7 @@ function getOrCreateSelfSignedCert(): { key: string; cert: string } {
 interface SessionListenerRefs {
   terminal: (data: string) => void;
   clearTerminal: () => void;
+  needsRefresh: () => void;
   message: (msg: ClaudeMessage) => void;
   error: (error: string) => void;
   completion: (result: string, cost: number) => void;
@@ -4169,6 +4170,7 @@ NOW: Generate the implementation plan for the task above. Think step by step.`;
       if (listeners) {
         session.off('terminal', listeners.terminal);
         session.off('clearTerminal', listeners.clearTerminal);
+        session.off('needsRefresh', listeners.needsRefresh);
         session.off('message', listeners.message);
         session.off('error', listeners.error);
         session.off('completion', listeners.completion);
@@ -4238,6 +4240,11 @@ NOW: Generate the implementation plan for the task above. Think step by step.`;
         this.broadcast('session:clearTerminal', { id: session.id });
       },
 
+      needsRefresh: () => {
+        // Tell clients to reload the terminal buffer (e.g., after OpenCode TUI stabilizes)
+        this.broadcast('session:needsRefresh', { id: session.id });
+      },
+
       message: (msg: ClaudeMessage) => {
         this.broadcast('session:message', { id: session.id, message: msg });
       },
@@ -4436,6 +4443,7 @@ NOW: Generate the implementation plan for the task above. Think step by step.`;
     // Attach all listeners to the session
     session.on('terminal', listeners.terminal);
     session.on('clearTerminal', listeners.clearTerminal);
+    session.on('needsRefresh', listeners.needsRefresh);
     session.on('message', listeners.message);
     session.on('error', listeners.error);
     session.on('completion', listeners.completion);
@@ -5611,6 +5619,7 @@ NOW: Generate the implementation plan for the task above. Think step by step.`;
       if (listeners) {
         session.off('terminal', listeners.terminal);
         session.off('clearTerminal', listeners.clearTerminal);
+        session.off('needsRefresh', listeners.needsRefresh);
         session.off('message', listeners.message);
         session.off('error', listeners.error);
         session.off('completion', listeners.completion);