Mission Control Turbo: macOS multitasking turbocharged

Add launch-at-login, install to /Applications, generate app icon master

Launch at login uses SMAppService.mainApp and only registers when the bundle runs from /Applications, so dev builds don't pin the login item to the wrong path. build.sh now installs into /Applications after signing so permission grants and the login item resolve to a stable location. App icon is rendered by a small CoreGraphics script and cached as AppIcon.icns. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>