Per mod/docs/optimize-layer-design.md.
Status header: was 'черновик на согласование (2026-10-09)', now
'Этап 1 готов, Этап 2 + начало Этапа 3 готовы (2026-10-10)'.
New 'История изменений' section: three dated entries (Stage 1, Stage 2,
Stage 3 partial) listing files / tests / patch references.
Stages section: each line now carries a status icon (✅/🔄/❌), a completion
date, and a one-line summary of what shipped. Stage 3 partial lists what's
done (RenderBackendOps + GlRenderBackendOps + 3 GL mixins) and what's still
left (FrameFence, SharedDepthFbos, SkinAtlas, AnimFreeze, ItemLod,
LivingEntityLodMixin, ParticleMixin, SpawnerRendererMixin, etc.).
New 'Оценки для Этапов 3-4' section: rough effort estimates for the
remaining Stage 3 work (~25 mixins + ~8 helpers, 3-4 work sessions) and
Stage 4 (6 Vulkan items, profiling-driven, 1+ session for vkCmdCopyImage
which is needed for SkinAtlas to work on Vulkan).
Per mod/docs/optimize-layer-design.md Stage 1: pure helpers and mixin-contract
interfaces for the Optimize module, plus the OptimizeToggles engine-side state
holder and nine new toggles in Optimize. GL/Vulkan hooks are Stages 3-4.
