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/spec/entities.toml

@@ -380,6 +380,21 @@ op = "SetAttribute"
 args = [{ name = "tag", ty = "&str" }, { name = "value", ty = "&str" }]
 returns = "()"
 
+# ============================================================================
+# ATTRIBUTE-DEFINITION FAMILY (phase 3-ii) — in-block attribute definitions
+# ============================================================================
+[[family]]
+name = "AttributeDefinition"
+acadrust_variant = "AttributeDefinition"
+handle = "Entity"
+collection = "entities"
+description = "In-block attribute definition (ATTDEF): tag/prompt/default at an insertion point."
+
+[[family.constructor]]
+name = "create_attribute_definition"
+args = [{ name = "tag", ty = "&str" }, { name = "prompt", ty = "&str" }, { name = "default_value", ty = "&str" }, { name = "insertion_point", ty = "[f64; 3]" }, { name = "height", ty = "f64" }, { name = "rotation", ty = "f64" }]
+op = "CreateAttributeDefinition"
+
 # ============================================================================
 # PAPER-SPACE FAMILY (phase 4) — viewports
 # ============================================================================