Remove rename blocking during streaming

With stable IDs, workspace rename no longer requires moving files or
changing workspace ID. Rename only updates:
- metadata.name (display name)
- Symlink (~/.cmux/src/project/name → workspaceId)

Session directory (~/.cmux/sessions/workspaceId) remains unchanged,
so active streams can continue writing safely.

Changes:
- Remove isStreaming check from WORKSPACE_RENAME handler
- Remove "should block rename during active stream" test
- Simplifies UX: no more "Press Esc first" error

Benefits:
- Users can organize workspaces without interrupting work
- One less artificial limitation
- Cleaner, simpler code (-38 lines)

Author: ammar-agent

src/services/ipcMain.ts

@@ -277,13 +277,6 @@ export class IpcMain {
             return Err(validation.error ?? "Invalid workspace name");
           }
 
-          // Block rename if there's an active stream
-          if (this.aiService.isStreaming(workspaceId)) {
-            return Err(
-              "Cannot rename workspace while stream is active. Press Esc to stop the stream first."
-            );
-          }
-
           // Get current metadata
           const metadataResult = await this.aiService.getWorkspaceMetadata(workspaceId);
           if (!metadataResult.success) {

tests/ipcMain/renameWorkspace.test.ts

@@ -223,43 +223,6 @@ describeIntegration("IpcMain rename workspace integration tests", () => {
     15000
   );
 
-  test.concurrent(
-    "should block rename during active stream and require Esc first",
-    async () => {
-      const { env, workspaceId, cleanup } = await setupWorkspace("anthropic");
-      try {
-        // Clear events before starting stream
-        env.sentEvents.length = 0;
-
-        // Start a long-running stream
-        void sendMessageWithModel(
-          env.mockIpcRenderer,
-          workspaceId,
-          "Run this bash command: for i in {1..60}; do sleep 0.5; done && echo done"
-        );
-
-        // Wait for stream to start
-        const startCollector = createEventCollector(env.sentEvents, workspaceId);
-        await startCollector.waitForEvent("stream-start", 10000);
-
-        // Try to rename during active stream - should be blocked
-        const renameResult = await env.mockIpcRenderer.invoke(
-          IPC_CHANNELS.WORKSPACE_RENAME,
-          workspaceId,
-          "new-name"
-        );
-        expect(renameResult.success).toBe(false);
-        expect(renameResult.error).toContain("stream is active");
-        expect(renameResult.error).toContain("Press Esc");
-
-        // Test passed - rename was successfully blocked during active stream
-      } finally {
-        await cleanup();
-      }
-    },
-    15000
-  );
-
   test.concurrent(
     "should fail to rename with invalid workspace name",
     async () => {