fix: keep the session menu in front after installing ControlFS

[lippdev]

What

Follow-up to #136. After installing ControlFS from the session menu, the app no longer opens it by itself.

Before, the end of the install called OpenControlFs(), which closed the menu and launched ControlFS. By then Windows didn't hand ControlFS the foreground, so in a Big Picture session the menu disappeared and ControlFS came up behind Big Picture (reported on 1.6.0-beta.5; the log shows ControlFS: instalado followed immediately by ControlFS: aberto).

Now the menu stays open and in front, the row says "Installed · press to open" (new ControlFsInstalled string in the three catalogs), and the next A opens ControlFS the usual way. The row goes back to its normal text the next time the menu opens.

Verification

• Unit tests: 325 pass locally; built locally on Windows (Debug, win-x64).
• Ran the debug build on the owner's PC with ControlFS uninstalled, menu in preview: A showed "Downloading… 23%" with the bar, the install finished in about 28 s with no installer window or UAC prompt, the menu stayed in the foreground with "Installed · press to open", and the next A opened ControlFS full screen in the foreground. The downloaded setup was deleted.
• Not checked: with a controller (keyboard only) and inside a Big Picture session, the case that was reported. Manual steps in docs/TESTING.md (1d).

🤖 Generated with Claude Code

[pullfrog]

✅ No new issues found.

Reviewed changes The review covers the ControlFS install-completion behavior, its localized row state, and the associated manual test and beta release metadata.

• Install completion The menu remains open after installation, shows an installed state, and leaves launching ControlFS to the next A press.
• Localization and manual test The new row text is added to all three catalogs, and the testing checklist reflects the new flow, including closing the menu during installation.
• Beta release metadata Both changelogs and the project version are updated to 1.6.0-beta.6.

  ^{｜ View workflow run ｜ Using gpt-6-luna ｜ 𝕏}