Fix Touch Bar hamburger settings toggle

[kilo-code-bot]

Summary

• Toggle the settings editor through the existing shell hide/summon paths instead of always reopening and repositioning it.
• Preserve the existing unsaved-changes confirmation and cancel pending window presentation when closing.
• Add QML regressions for open/hide/reopen, cancelling and confirming discard, and rapid-close presentation cleanup.

Closes #1

Validation

• Passed: eight backend model tests and four device-helper tests.
• Passed: git diff --check and bash -n tests/test-qml.sh.
• QML regression execution blocked: Quickshell (qs) is not installed in this environment.
• Native build blocked: node-gyp/undici assertion while downloading Node headers. The protocol test consequently fails because drm_backend.node is unavailable.
• Physical Touch Bar and Hyprland workspace scenarios could not be exercised in this container.