Refactor: enforce canonical messages/output YAML, normalize content_file, and expand fixture-based validation tests

profiles/generic.structured_events.yaml

@@ -9,7 +9,7 @@ inputs:
   - name: glossary
     required: false
     content_type: text/yaml
-templates:
+messages:
   - role: system
     content: |
       Return only JSON following the requested schema.
@@ -23,8 +23,7 @@ templates:
 
       Glossary:
       {{input "glossary"}}
-output_format: json
-validation:
+output:
   format: json
   validation_mode: json_schema
   schema_path: structured_events.schema.json