Fix double-launch flashing a port-in-use error

[MyNamesEMurray]

Summary

Launching Hype Ghost while it's already running no longer spawns a doomed second instance that errors with "port already in use" — it now just brings the running app to the foreground (recreating the window from tray mode, restoring it if minimized).

Changes

• Root cause: the single-instance lock existed, but app.quit() is asynchronous — and the app.whenReady().then(...) startup block was registered at top level regardless of the lock. The losing instance therefore still reached startServer(), collided on port 3777, and showed the EADDRINUSE dialog before its queued quit ever landed. The whenReady registration is now gated on holding the lock, so a second launch exits silently.
• Focus behavior (second-instance in the surviving app): restore if minimized, recreate the window if it was destroyed to tray, then show + focus — "open the program again" now simply means "show me the deck".

Verification

• Suite (45) + smoke green; syntax checked. The double-launch path itself is Electron-runtime-only (not exercisable in Linux CI): worth a ten-second manual check after release — launch the installed app, launch it again from the Start menu, expect the deck to pop to the front with no error dialog, once from the tray-only state too.

Risk & rollout

• Single-file change in the desktop shell; the smoke/CI path (HG_SMOKE) holds the lock as the only instance, unchanged.
• Rides as a patch (no bump trailer).

Checklist

• npm run smoke passes locally (or CI is green)
• Follows the design language in DESIGN.md (if UI changed)
• AI-labeling / "simulated viewers" guarantees intact (if bot output or overlay changed)
• Docs updated (README / config reference) if behavior or config changed
• Targets main

🤖 Generated with Claude Code

https://claude.ai/code/session_01FNRQP2h3GUQVThuE2KVBEu

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