Add PyObjC Cocoa UI (mac_cocoa.py) and update build to install pyobjc

Co-authored-by: Copilot <[email protected]>

build_mac.sh

@@ -11,7 +11,7 @@ source .venv/bin/activate
 
 pip install --upgrade pip setuptools wheel
 pip install -r requirements.txt
-pip install py2app
+pip install py2app pyobjc-framework-Cocoa
 
 # Build the macOS .app
 python3 setup.py py2app