ocs_doc_api: Phase 5 typed raster image create

- CreateRasterImage(RasterImageSpec) op (append-only).
- backend add_raster_image (RasterImage with file_path/insertion/u/v/size; the
  scene auto-registers the ImageDefinition on add_entity).
- facade create_raster_image; spec RasterImage constructor; api_reference +
  binding_schema regenerated; mocks + baseline.
- Test phase5_create_raster_image_registers_definition (asserts definition_handle
  auto-registered + 4-corner bounds) -> 610 host lib + 3 consistency green.
- Phase 5 complete.

crates/ocs_doc_api/spec/entities.toml

@@ -398,7 +398,12 @@ name = "RasterImage"
 acadrust_variant = "RasterImage"
 handle = "Entity"
 collection = "entities"
-description = "Raster image (read-mostly): GetEntity kind + coarse bounds (insertion + u*width + v*height); generic delete. No typed create in v1."
+description = "Raster image: create_raster_image(file_path, insertion, u, v, size) places an image (host auto-registers the ImageDefinition); bounds (4-corner bracket); delete."
+
+[[family.constructor]]
+name = "create_raster_image"
+args = [{ name = "file_path", ty = "&str" }, { name = "insertion_point", ty = "[f64; 3]" }, { name = "u_vector", ty = "[f64; 3]" }, { name = "v_vector", ty = "[f64; 3]" }, { name = "size", ty = "[f64; 2]" }]
+op = "CreateRasterImage"
 
 [[family]]
 name = "Table"