Pragtical 3.12 Adds SDL GPU Backend: Sub-50MB Editor Beats CPU Path by Up to 3.36x

Pragtical 3.12 adds an opt-in SDL GPU backend that cuts cold-glyph text rendering by 3.36x over the CPU surface renderer in this sub-50MB open source code editor. The backend uses atlas-backed glyph caching and command-buffer batching across Direct3D 12, Metal, and Vulkan. Version 3.12 also gates project module loading behind trust prompts.