Add bambustudio-bin, Bambu Studio, to the fast ring

Bambu Studio is the official slicer for Bambu Lab printers. Linux builds
are GitHub AppImages with a changing timestamp in the filename, so this
tracks the AUR bambustudio-bin package that already resolves those
assets, and puts it on the fast ring so stable users get updates with
omarchy update.

Two small Omarchy patches: skip stripping the extracted AppImage, and
clear the AppImage ELF magic byte so --appimage-extract works in the
build container. The desktop entry is labeled Bambu Studio and grouped
under Graphics.

Validation: bin/add-package + bin/sync-aur reapply the patches; AUR +
.omarchy reproduces the checked-in tree. Built and launched the 2.8.2.61
AppImage on Omarchy 4.0.3 (x86_64); bambu-studio --help reports
BambuStudio-02.08.02.61. AUR is currently 02.08.02.60; the next AUR bump
will sync through.

pkgbuilds/bambustudio-bin/BambuStudio.desktop

@@ -0,0 +1,12 @@
+[Desktop Entry]
+Name=Bambu Studio
+GenericName=3D Printing Software
+Comment=Slicer for Bambu Lab and other 3D printers
+Exec=/usr/bin/bambu-studio %U
+Icon=BambuStudio
+Terminal=false
+Type=Application
+Categories=Graphics;3DGraphics;Engineering;
+MimeType=x-scheme-handler/bambustudio;model/stl;application/vnd.ms-3mfdocument;application/prs.wavefront-obj;application/x-amf;
+Keywords=3D;Printing;Slicer;gcode;stl;3mf
+StartupWMClass=bambu-studio