chore: checkpoint web Blender migration source, tools and docs

Accumulated uncommitted work: GHOST Web backend, WebGL/GPU web layer,
web workflow engine and protocol, tooling, docs and task records.
Large generated evidence, user-testing archives, build snapshots and
imported test assets remain untracked.

Co-Authored-By: Claude Code <noreply@anthropic.com>

tools/web/openusd-static-python.cmake

@@ -0,0 +1,27 @@
+# Included after the original OpenUSD module declarations. Derive both the
+# linker inputs and CPython registrations from exactly the wrappers built.
+if(NOT PXR_WEB_STATIC_PYTHON)
+  return()
+endif()
+if(NOT EMSCRIPTEN OR BUILD_SHARED_LIBS)
+  message(FATAL_ERROR "PXR_WEB_STATIC_PYTHON requires the static Emscripten build")
+endif()
+get_property(modules GLOBAL PROPERTY PXR_WEB_PYTHON_MODULES)
+set(header "#pragma once\n#include <Python.h>\n")
+set(registrations "")
+set(libraries "get_filename_component(_pxr_web_root \"\${CMAKE_CURRENT_LIST_DIR}/..\" ABSOLUTE)\nset(WEB_USD_PYTHON_LIBRARIES)\n")
+foreach(module IN LISTS modules)
+  string(REPLACE "|" ";" fields "${module}")
+  list(GET fields 0 package)
+  list(GET fields 1 wrapper)
+  string(APPEND header "extern \"C\" PyObject *PyInit_${wrapper}();\n")
+  string(APPEND registrations
+    "  if (PyImport_AppendInittab(\"pxr.${package}.${wrapper}\", PyInit_${wrapper}) < 0) return -1;\n")
+  string(APPEND libraries
+    "list(APPEND WEB_USD_PYTHON_LIBRARIES \"\${_pxr_web_root}/lib/python/pxr/${package}/${wrapper}${CMAKE_STATIC_LIBRARY_SUFFIX}\")\n")
+endforeach()
+string(APPEND header "inline int web_engine_register_usd_python()\n{\n${registrations}  return 0;\n}\n")
+file(GENERATE OUTPUT "${PROJECT_BINARY_DIR}/web_engine_usd_python.hh" CONTENT "${header}")
+file(GENERATE OUTPUT "${PROJECT_BINARY_DIR}/webengine-pxr.cmake" CONTENT "${libraries}")
+install(FILES "${PROJECT_BINARY_DIR}/web_engine_usd_python.hh" DESTINATION include)
+install(FILES "${PROJECT_BINARY_DIR}/webengine-pxr.cmake" DESTINATION cmake)