## Description
This PR makes `codex remote-control` behave like a foreground CLI
command by default. Running it now starts remote control, waits for
readiness, prints a clear status message with the machine name, and
stays alive until Ctrl-C.
Users who want daemon behavior can use `codex remote-control start`, and
`codex remote-control stop` now prints concise human-readable output.
`--json` remains available for scripts.
Implementation-wise, this now verifies the real app-server state instead
of just assuming startup worked. The CLI starts or connects to
app-server, probes its control socket, calls the `remoteControl/enable`
API, and waits for the remote-control status response/notification
before printing success.
For daemon mode, `codex remote-control start` also reports which managed
app-server binary was used, including its path and best-effort `codex
--version`, so failures are easier to diagnose.
## Examples
Example output:
```
> codex remote-control
Starting app-server with remote control enabled...
This machine is available for remote control as com-97826.
Press Ctrl-C to stop.
```
Error case using daemon (currently expected based on our publicly
released CLI version):
```
> ./target/debug/codex remote-control start
Starting app-server daemon with remote control enabled...
Error: app server did not become ready on /Users/owen/.codex/app-server-control/app-server-control.sock
Daemon used app-server:
path: /Users/owen/.codex/packages/standalone/current/codex
version: 0.130.0
Managed app-server stderr (/Users/owen/.codex/app-server-daemon/app-server.stderr.log):
error: unexpected argument '--remote-control' found
Usage: codex app-server [OPTIONS] [COMMAND]
For more information, try '--help'.
Caused by:
0: failed to connect to /Users/owen/.codex/app-server-control/app-server-control.sock
1: No such file or directory (os error 2)
```
## What changed
- `codex remote-control` now runs remote control in the foreground and
prints a Ctrl-C stop hint.
- `codex remote-control start` starts the daemon and waits for remote
control readiness before reporting success.
- `codex remote-control stop` reports stopped/not-running status in
plain language.
- Startup failures now include recent managed app-server stderr to make
daemon issues easier to diagnose.
- Added coverage for CLI output, readiness waiting, foreground shutdown,
and stderr log tailing.
Owen Lin