Anime4K v4.0.1 assets

Upstream: https://github.com/bloc97/Anime4K
Tag: v4.0.1
Commit: 4029bf701ecaa15f163cdc49cffe5501c1acf410
License: MIT (see ANIME4K_LICENSE.txt)

Runtime asset manifest and SHA-256 values are declared in
lib/src/features/playback/anime4k_assets.dart. Files are copied into a
versioned private directory and verified before mpv loads them.

Upstream paths:
- glsl/Restore/Anime4K_Clamp_Highlights.glsl
- glsl/Restore/Anime4K_Restore_CNN_Soft_S.glsl
- glsl/Restore/Anime4K_Restore_CNN_M.glsl
- glsl/Restore/Anime4K_Restore_CNN_L.glsl
- glsl/Upscale/Anime4K_Upscale_CNN_x2_S.glsl
- glsl/Upscale/Anime4K_Upscale_CNN_x2_M.glsl
