ocs_doc_api: Phase 3-ii — typed AttributeDefinition create (Phase 3 complete)

- CreateAttributeDefinition(AttributeDefinitionSpec) op (append-only).
- backend add_attribute_definition (ATTDEF tag/prompt/default/insertion/height/rotation).
- facade create_attribute_definition; entity_kind_name AttributeDefinition/AttributeEntity.
- spec AttributeDefinition family; api_reference + binding_schema regenerated; mocks + baseline.
- Test phase3ii_create_attribute_definition -> 614 host lib + 3 consistency green.

crates/ocs_doc_api/tests/mock_backend.rs

@@ -140,6 +140,12 @@ impl DocApiBackend for MockBackend {
     fn dimension_measurement(&self, id: ObjectId) -> ApiResult<f64> {
         self.dimension_measurements.get(&id).copied().ok_or(ApiError::UnknownId(id))
     }
+    fn add_attribute_definition(&mut self, spec: &ocs_doc_api::ops::AttributeDefinitionSpec) -> ApiResult<ObjectId> {
+        if spec.tag.is_empty() {
+            return Err(ApiError::validation("CreateAttributeDefinition", "empty tag"));
+        }
+        Ok(self.alloc("AttributeDefinition"))
+    }
     fn set_attribute(&mut self, id: ObjectId, tag: &str, value: &str) -> ApiResult<()> {
         if !self.entity_exists(id) {
             return Err(ApiError::UnknownId(id));

crates/ocs_doc_api/tests/spec_wire_consistency.rs

@@ -67,6 +67,9 @@ fn operation_variants() -> Vec<String> {
         Operation::CreateDimensionRadius(ocs_doc_api::ops::DimensionRadialSpec { center: [0.0; 3], point: [0.0; 3] }),
         Operation::CreateDimensionDiameter(ocs_doc_api::ops::DimensionRadialSpec { center: [0.0; 3], point: [0.0; 3] }),
         Operation::CreateDimensionAngular(ocs_doc_api::ops::DimensionAngularSpec { vertex: [0.0; 3], first_point: [0.0; 3], second_point: [0.0; 3], arc_location: [0.0; 3] }),
+        Operation::CreateAttributeDefinition(ocs_doc_api::ops::AttributeDefinitionSpec {
+            tag: String::new(), prompt: String::new(), default_value: String::new(), insertion_point: [0.0; 3], height: 0.0, rotation: 0.0,
+        }),
     ];
     // Derive the variant names by serializing a probe of each and reading the
     // bincode variant index -> name map is not available; instead match by
@@ -159,6 +162,7 @@ const OPERATION_BASELINE: &[&str] = &[
     "CreateDimensionRadius",
     "CreateDimensionDiameter",
     "CreateDimensionAngular",
+    "CreateAttributeDefinition",
 ];
 
 /// Recorded baseline of the `Query` variant order.