feat: render `.clip` thumbnails.

[Sola-ris]

Summary

Add support for rendering .clip thumbnails. Fixes https://github.com/TagStudioDev/TagStudio/issues/1146

.clip project files embedd an SQLite database at the end of the file which contains the thumbnail in the CanvasPreview table.

Before

After

Sources for the file format

• clip-studio-paint-layers-extractor
• The test file opened in a text editor

File used for testing

Drawing by Surendra Rajawat hosted on Clip Studio Paint's website

Tasks Completed

• Platforms Tested:
  • [ ] Windows x86
  • [ ] Windows ARM
  • [ ] macOS x86
  • [ ] macOS ARM
  • [x] Linux x86
  • [ ] Linux ARM
• Tested For:
  • [x] Basic functionality
  • [ ] PyInstaller executable

[Pheubel]

I just tried this PR on windows 10 (x86_64) with a simple illustration i quickly drew together and an illustration that uses a newer version of CSP and it works like expected, this will be a nice addition for my artist friend. 👍

[TrigamDev]

Checked and it appears to be working as expected