fix: remove deprecated strum::ToString and fix HashMap type conversion

Co-authored-by: aider (openai/andrew/openrouter/deepseek/deepseek-chat-v3.1) <aider@aider.chat>

src/services/meta_service.rs

@@ -66,7 +66,7 @@ impl MetaService {
                         let outputs: std::collections::HashMap<String, serde_yaml::Value> = config
                             .outputs
                             .iter()
-                            .map(|(k, v)| (k.clone(), v.clone()))
+                            .map(|(k, v)| (k.clone(), serde_yaml::Value::String(v.clone())))
                             .collect();
                         
                         (Some(options), Some(outputs))