Studio: Implement studio site stop CLI command

[bcotrim]

Related issues

• Fixes STU-951

Proposed Changes

• Implemented studio site stop CLI command for gracefully stopping local WordPress sites
• Added graceful shutdown mechanism via IPC message to child process with 5s timeout before falling back to PM2 delete
• Clears latestCliPid from appdata

Testing Instructions

• Build the CLI: npm run cli:build
• Create a test site: node dist/cli/main.js site create --path path
• Stop the site: node dist/cli/main.js site stop --path path
• Verify the site is stopped and no longer running
• Verify the latestCliPid is added on start and removed when site is stopped
• Test error scenarios: try stopping a non-existent site, already stopped site

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[github-actions]

📊 Performance Test Results

Comparing 3cb5785 vs trunk

site-editor

Metric	trunk	3cb5785	Diff	Change
load	16402.00 ms	15443.00 ms	-959.00 ms	🟢 -5.8%

site-startup

Metric	trunk	3cb5785	Diff	Change
siteCreation	20163.00 ms	21183.00 ms	+1020.00 ms	🔴 5.1%
siteStartup	6939.00 ms	7965.00 ms	+1026.00 ms	🔴 14.8%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change

[fredrikekelund]

This is great overall 👍 My only issues with the implementation were that sendStopMessage was unnecessary, and that we shouldn't use the as keyword for any of the types from cli/lib/types/wordpress-server-ipc.ts. I went ahead and pushed a fix for both of those issues.

There's one more thing I think we should look into before landing this, and that is stopping the proxy server if no remaining running sites depend on it.

[fredrikekelund]

Let's use getSiteByFolder here once #2134 has landed.

[fredrikekelund]

Suggested change

	builder: ( yargs ) => {
	return yargs;
	},

[bcotrim]

@fredrikekelund thanks for the review! I've updated the code to stop the proxy if no longer needed.
This should be ready for another review