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>

web/tests/fixtures/create-mesh-editor-input.py

@@ -0,0 +1,25 @@
+import bpy
+import pathlib
+
+root = pathlib.Path(__file__).resolve().parents[3]
+bpy.ops.wm.open_mainfile(filepath=str(root / "tests/files/web/basic_scene.blend"))
+mesh = bpy.data.objects["BasicCube"].data
+# Reverse one face of the closed cube so normal repair has observable work.
+vertices = [tuple(vertex.co) for vertex in mesh.vertices]
+faces = [tuple(polygon.vertices) for polygon in mesh.polygons]
+faces[0] = tuple(reversed(faces[0]))
+mesh.clear_geometry()
+mesh.from_pydata(vertices, [], faces)
+mesh.update()
+uv = mesh.uv_layers.active or mesh.uv_layers.new(name="UVMap")
+for corner in uv.data:
+    corner.uv = (0.125, 0.875)
+bridge = bpy.data.meshes.new("WebBridgeMesh")
+bridge.from_pydata([(-1, -1, 0), (1, -1, 0), (1, 1, 0), (-1, 1, 0),
+                    (-1, -1, 2), (1, -1, 2), (1, 1, 2), (-1, 1, 2)], [],
+                   [(3, 2, 1, 0), (4, 5, 6, 7)])
+bridge.update()
+obj = bpy.data.objects.new("WebBridgeObject", bridge)
+bpy.context.scene.collection.objects.link(obj)
+obj.location.x = 4
+bpy.ops.wm.save_as_mainfile(filepath=str(root / "tests/files/web/mesh_editor_scene.blend"), check_existing=False)