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>

blender-5.2.0/source/blender/python/intern/bpy.cc

@@ -751,7 +751,9 @@ static PyObject *bpy_import_test(const char *modname)
     Py_DECREF(mod);
   }
   else {
+#ifndef __EMSCRIPTEN__
     PyErr_Print();
+#endif
   }
 
   return mod;
@@ -812,11 +814,21 @@ void BPy_init_modules(bContext *C)
     BLI_assert(PyDict_GET_SIZE(bpy_types_dict_dummy) == 0);
     Py_DECREF(bpy_types_dict_dummy);
 
+    if (!bpy_types_module_py) {
+      BPY_rna_types_dict_set(nullptr);
+      return;
+    }
+
     PyObject *bpy_types_module_py_dict = PyModule_GetDict(bpy_types_module_py);
     BPY_rna_types_dict_set(bpy_types_module_py_dict);
   }
   PyModule_AddObject(mod, "data", BPY_rna_module());
   BPY_rna_types_finalize_external_types(bpy_types);
+  if (PyErr_Occurred()) {
+    /* Preserve the original metaclass/allocation exception for the embedded
+     * interpreter caller instead of continuing with partially built types. */
+    return;
+  }
 
   PyModule_AddObject(mod, "props", BPY_rna_props());
   PyModule_AddObject(mod, "ops", BPY_operator_module());