Move canvas stroke commit GL mappings to renderer gl

docs/modernization/build-inventory.md

@@ -218,6 +218,9 @@ Known local toolchain state:
   format/type, stroke mixer depth/scissor/blend state, saved viewport and
   clear-state queries, active texture units, fallback 2D texture unbind
   targets, and stroke background copy targets.
+  Canvas stroke commit also consumes backend-owned saved viewport/clear/blend
+  state, history readback format/type, active texture units, fallback 2D
+  texture unbind targets, and layer compositing copy targets.
 - `windows-msvc-vcpkg-headless` validates manifest install/configure/build/test
   for the current headless component matrix; see DEBT-0007 for remaining app
   and platform triplet migration.

docs/modernization/roadmap.md

@@ -762,6 +762,9 @@ Results:
   and blend state, saved viewport/clear-state queries, active texture units,
   fallback 2D texture unbinds, and stroke background copy targets through the
   renderer GL backend mapping.
+- Canvas stroke commit now routes saved viewport/clear/blend state, history
+  readbacks, active texture units, fallback 2D texture unbinds, and layer
+  compositing copy targets through the renderer GL backend mapping.
 - Known remaining warnings: legacy project/vendor diagnostics, Visual Studio
   vcpkg-manifest warning, `LNK4099` missing libyuv PDBs, and `LNK4098` runtime
   library conflict from retained vendor binaries.