Fix Codex Remote thread writer conflicts

agents.py

@@ -349,6 +349,11 @@ def start_agent(cfg, agent, *, force=False):
         if backend.get("remote_control"):
             parts.append(_render_template(backend.get("remote_control_flag",
                                           "--remote-control '{session}'"), {"session": session}))
+        if backend.get("remote_addr"):
+            parts.append(_render_template(backend.get("remote_addr_flag", "--remote '{addr}'"), {
+                "addr": backend["remote_addr"], "session": session, "model": model,
+                "dir": shlex.quote(cwd),
+            }))
         if model:
             parts.append(_render_template(backend.get("model_flag", "--model '{model}'"), {"model": model}))
         if backend.get("flags"):
@@ -356,8 +361,8 @@ def start_agent(cfg, agent, *, force=False):
         parts.append(f"\"$(cat '{kf}')\"")
         cmd = " ".join(p for p in parts if p)
         # Some interactive CLIs need an idempotent service prepared before their TUI starts.
-        # Codex Remote Control is one such service: `remote-control start` ensures the shared
-        # app-server daemon is enrolled and connected, then the pane runs the ordinary Codex TUI.
+        # The Codex backend starts the shared app-server here, while remote_addr above makes the
+        # pane's TUI a client of that daemon so both local and Remote UIs share one thread writer.
         if backend.get("preamble"):
             preamble = _render_template(backend["preamble"], {
                 "bin": backend["bin"], "session": session, "model": model,