Route RTT framebuffer binding through renderer GL

docs/modernization/build-inventory.md

@@ -468,9 +468,10 @@ Known local toolchain state:
   setup, tested saved-state snapshot/restore dispatch consumed by the retained
   `gl_state` utility, tested texture lifecycle/readback dispatch consumed by
   the retained `Texture2D` utility, tested framebuffer blit/readback dispatch
-  consumed by retained `RTT` resize/copy/readback paths, plus renderer API to
-  OpenGL token mapping and command-planning contracts used by the OpenGL parity
-  work.
+  consumed by retained `RTT` resize/copy/readback paths, tested framebuffer
+  bind/restore dispatch consumed by retained `RTT` render-target pass entry
+  and exit paths, plus renderer API to OpenGL token mapping and command-planning
+  contracts used by the OpenGL parity work.
 - `pano_cli plan-cloud-upload` exposes `pp_app_core` cloud upload availability,
   new-document warning, publish prompt, and save-before-upload planning as JSON;
   the live cloud upload command consumes the same start contract before

docs/modernization/roadmap.md

@@ -547,6 +547,9 @@ resource lifecycle path behind the renderer backend boundary.
 Legacy `RTT` resize/copy blits and byte/float framebuffer readbacks now execute
 through tested `pp_renderer_gl` framebuffer dispatch contracts with draw/read
 framebuffer binding restore handled by the backend helper.
+Legacy `RTT::bindFramebuffer` and `RTT::unbindFramebuffer` now use tested
+`pp_renderer_gl` draw/read framebuffer binding snapshot and restore contracts,
+moving render-target pass entry/exit state management behind the backend.
 Windows RenderDoc frame capture hooks now also dispatch through
 `PlatformServices`, keeping capture integration in the platform service while
 leaving non-Windows adapters as no-ops.