fix: open external links in the OS browser on Standalone

[rafaellehmkuhl]

Opens external links in the OS preferred browser instead of in an Electron window.

To test it, just open /menu/about and click the links there.

Fixes #2612

[github-actions]

Automated PR Review (Claude)

0. Summary

Verdict: READY TO MERGE

This single-commit PR fixes external links (http/https/mailto) in the Electron (Standalone) build so they open in the OS default browser instead of spawning a new BrowserWindow. It adds a setWindowOpenHandler for target="_blank" / window.open links and a will-navigate listener for in-page navigations, both in src/electron/main.ts. The change is small, well-scoped, and uses Electron's recommended APIs correctly.

1. Correctness & Implementation Bugs — ✅

2. AGENTS.md Adherence — ✅

3. Security — ✅

4. Performance — ✅

5. UI / UX — ✅

6. Code Quality & Style — ✅

7. Commit Hygiene — ✅

8. Tests — ✅

9. Documentation — ✅

10. Nitpicks / Optional

10.1 nit — src/electron/main.ts (diff line 17): The will-navigate handler checks url.startsWith('http:') || url.startsWith('https:') after already confirming !isInternal. Since isInternal is only true for file: or the dev-server URL, the http/https guard is redundant for production (where non-internal is always http/https). It's still a reasonable belt-and-suspenders check for safety, so no action needed — just noting it.

Generated by Claude. This is advisory; a human reviewer must still approve.

[rafaellehmkuhl]

Automated PR Review (Claude)

Will ignore the nit.