[Bug] FFmpeg fails on Mac Silicon: Bad CPU type in executable (Apple Silicon arm64 incompatibility)

[KYatoo]

Description

When running YouTube 4K Downloader on Mac Mini M4 (Apple Silicon), the log shows the following error:

FFmpeg exception: [Errno 86] Bad CPU type in executable: '/Applications/YouTube 4K Downloader.app/Contents/Resources/ffmpeg'

This prevents video downloading/processing from working properly.
Maybe installing Rosetta would solve the problem, since it's an emulation layer that can run ffmpeg compiled for that architecture, but ideally we'd get a completely native build of arm64

Suggested Fix

1. Bundle a universal (x86_64 + arm64) ffmpeg binary in future releases
2. Add an option for users to manually specify an external ffmpeg path

Environment

Model Name: Mac mini
Chip: Apple M4
Memory: 16 GB
System Version: macOS 26.3 (25D125)
Kernel Version: Darwin 25.3.0