fix(os-service): use pathToFileURL for cross-platform log folder path

[MattPua]

Summary

Follow-up to #3005. Fixes showLogFolder to produce a valid file URI on all platforms.

• file://${path} breaks on Windows (C:\... → file://C:\..., invalid)
• pathToFileURL(path).href (Node built-in) handles this correctly on all platforms
• Adds a test asserting the launcher is called with a file:// URL

Danger level: 1/5

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Created with PostHog Code

[github-actions]

React Doctor found no issues in the changed files. 🎉

_{Reviewed by React Doctor for commit 7efc24d.}

[greptile-apps]

_{Reviews (1): Last reviewed commit: "fix(os-service): use pathToFileURL for c..." | Re-trigger Greptile}

[greptile-apps]

The assertion only checks the file:// protocol prefix, but the mock already sets logFolderPath: "/logs" — a deterministic value. On any platform pathToFileURL("/logs").href returns "file:///logs", so the test could assert the complete URL and thereby also verify that the correct path was forwarded to pathToFileURL. As written, the test would pass even if showLogFolder called pathToFileURL("") or any other path.

Suggested change

	expect(urlLauncher.launch).toHaveBeenCalledWith(
	expect.stringMatching(/^file:\/\//),
	);
	expect(urlLauncher.launch).toHaveBeenCalledWith("file:///logs");

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

[MattPua]

Merged into #3031.