feat: add sendToClaude helper and wait-for-event tool

- Add sendToClaude() function to browser helper that shows confirmation
- Add wait-for-event.sh script for watching server output (tail -f | grep -m 1)
- Enables clean event-driven loop: background bash waits for event, completion triggers Claude's turn

lib/brainstorm-server/helper.js

@@ -87,10 +87,28 @@
     }, 500); // 500ms debounce
   });
 
+  // Send to Claude - triggers server to exit and return all events
+  function sendToClaude(feedback) {
+    send({
+      type: 'send-to-claude',
+      feedback: feedback || null
+    });
+    // Show confirmation to user
+    document.body.innerHTML = `
+      <div style="display: flex; align-items: center; justify-content: center; height: 100vh; font-family: system-ui, sans-serif;">
+        <div style="text-align: center; color: #666;">
+          <h2 style="color: #333;">✓ Sent to Claude</h2>
+          <p>Return to the terminal to see Claude's response.</p>
+        </div>
+      </div>
+    `;
+  }
+
   // Expose for explicit use if needed
   window.brainstorm = {
     send: send,
-    choice: (value, metadata = {}) => send({ type: 'choice', value, ...metadata })
+    choice: (value, metadata = {}) => send({ type: 'choice', value, ...metadata }),
+    sendToClaude: sendToClaude
   };
 
   connect();