Umbra Studio v0.22.1

Model Installers

• Made Install-Umbra-UI-Models.bat open the complete interactive image-model
  prerequisite selector instead of the separate core support-model downloader.
• Added explicitly named Windows and Linux support-model launchers for the
  detailer, SAM, upscaling, interpolation, and reference-conditioning packs.
• Added bounded remote-source validation for every model requirement without
  downloading the complete weights.
• Made cancellation discard the entire incomplete download instead of retaining
  resumable partial model data. Valid size/hash matches are kept, while invalid
  existing files are replaced from byte zero.