Port to 26.2 + Vulkan API Support

[Walksy]

Adds support for 26.2 and the new Vulkan API added to this version. Changes:

• Migrated broken Blaze3D/client APIs (render target, GpuBuffer.map, GpuFormat, PrimitiveTopology, drawIndexed, GuiRenderer ctor, etc.)
  • Vulkan pipeline fixes (bind-group layouts, dropped unused Projection uniform, color target state)
• Other small changes to do with 26.2

I recently implemented a modified version of ReGlass into a project I'm working on, and since I had to create it for 26.2 I figured I should share the changes for the original repo. Love the project!

[RedxAx]

Thanks for taking the time, and congrats for your first PR!
Surface level review LGTM, I'll need to test it in-game, I'll do that after I finish my finals (3 days).