Switch from building a onefile executable to a onedir executable and app bundle.
The onefile executable is less efficient because it needs to extract resources
into a temp directory on every run, and it will no longer be supported as part
of an app bundle in future versions of pyinstaller.
Skip installing config and inference files under /usr, they will be referenced
from within the app bundle.
Use a plist when calling pkgbuild to avoid the macOS installer "relocating"
the app bundle to arbitrary locations, which breaks the "ramalama" symlink.
Signed-off-by: Mike Bonnet <mikeb@redhat.com>