#7155: fix(gateway): use kill SIGTERM instead of bootout for stop

## Problem `openclaw gateway stop` uses `launchctl bootout` which completely unloads the LaunchAgent from launchd. This means after stopping, users must run: ```bash openclaw gateway install && openclaw gateway start ``` Instead of just: ```bash openclaw gateway start ``` ## Solution Replace `launchctl bootout` with `launchctl kill SIGTERM` in `stopLaunchAgent()`. This: - Stops the process gracefully (SIGTERM) - Keeps the LaunchAgent loaded in launchd - Allows `start` to work immediately via `kickstart` ## Testing 1. `openclaw gateway stop` → service stops but stays loaded 2. `openclaw gateway start` → service restarts without install ## Notes - `bootout` is still used in `uninstallLaunchAgent()` where full removal is intended - `kill` only affects running services; error handling for not-loaded cases is preserved <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR changes the macOS launchd stop behavior for the gateway LaunchAgent: `stopLaunchAgent()` now uses `launchctl kill SIGTERM` instead of `launchctl bootout`, so the agent remains loaded in launchd and can be restarted immediately via `kickstart` without requiring a reinstall. The change is localized to `src/daemon/launchd.ts` and preserves the previous pattern of ignoring certain non-zero `launchctl` results via `isLaunchctlNotLoaded`, while continuing to use `bootout`/`unload` for full removal in uninstall flows. <h3>Confidence Score: 4/5</h3> - This PR is reasonably safe to merge, with a small behavioral edge case around stop-idempotency when the service isn’t running. - The change is small and targeted (one command swap plus messaging), but `launchctl kill` has different non-zero exit behaviors than `bootout`, and the current “not loaded” matcher may not treat common “already stopped” cases as non-fatal, which could regress `openclaw gateway stop` for some macOS versions/states. - src/daemon/launchd.ts (stopLaunchAgent error classification) <!-- greptile_other_comments_section --> _{(5/5) You can turn off certain types of comments like style [here](https://app.greptile.com/review/github)!} <!-- /greptile_comment -->