feat: Add LOCAL variable support for responses with UTF-8 JSON encoding.

Description: This feature adds support for UTF-8 encoding in JSON responses, allowing for proper handling of special characters and emojis.

- Implement unit tests for UTF-8 encoding in various model providers including Gemini, OpenAI, and OpenAI Compatible.
- Validate UTF-8 support in token counting, content generation, and error handling.
- Introduce tests for JSON serialization ensuring proper handling of French characters and emojis.
- Create tests for language instruction generation based on locale settings.
- Validate UTF-8 handling in workflow tools including AnalyzeTool, CodereviewTool, and DebugIssueTool.
- Ensure that all tests check for correct UTF-8 character preservation and proper JSON formatting.
- Add integration tests to verify the interaction between locale settings and model responses.

tools/consensus.py

@@ -512,7 +512,10 @@ of the evidence, even when it strongly points in one direction.""",
                     "provider_used": provider.get_provider_type().value,
                 }
 
-                return [TextContent(type="text", text=json.dumps(response_data, indent=2))]
+                return [TextContent(
+                    type="text", 
+                    text=json.dumps(response_data, indent=2, ensure_ascii=False)
+                )]
 
         # Otherwise, use standard workflow execution
         return await super().execute_workflow(arguments)