Prefer automatic hardware video decoding on macOS

[darioriccio]

Summary

• request score video decoding mode Auto in both Domeport packages
• keep DOMEPORTPRO_BASIC=1 confined to the basic package
• give the full package its own environment file

This uses the generic environment override proposed in ossia/score#2196. The FFmpeg packet/frame draining fix that prevents HEVC playback from freezing is proposed separately in ossia/score#2195. Syphon device creation with values returned by enumerateDevices() requires ossia/score#2197.

Verification

The combined macOS artifact built successfully in run 31439148108. Runtime checks on Apple M1 Pro verified:

• internal HEVC 4320x2160 playback advances continuously at about 52-54 FPS
• Syphon 3840x1920 input from VR Converter advances continuously
• equirectangular Syphon rendering reaches about 45 FPS
• domemaster Syphon rendering reaches about 52-55 FPS
• no HEVC missing-reference errors and no QVariant-to-QJSValue conversion error after selecting the real server

The render-target device-pixel-ratio correction remains isolated in #81.