[CI] Add MacOS Nightly build via Github Action

Goal

Add a workflow to create arm64 and x86_64 MacOS dmg files and upload them via FTPS.

This workflow can be run manually but is also started every day at 1am.

On Github side, you just need to define some secrets for the FTP. To do so, go to the Github repo settings and then on the Secrets and variables → Actions, add the following repository secret:

• ftp_server: Address of the FTP server (ftp.example.com format)
• ftp_user: FTP username
• ftp_password: FTP password

You also need to create repositories ./downloads/snap/macos/arm64 and ./downloads/snap/macos/arm64 because the CI need them to exist befoire uploading, they are not created by the CI.

Information

• Also add Python framework bin path for x86_64 to avoid missing pyinstaller when building on macos-15-intel Github Action runner
• Fix #12579 (closed)