feat(theme): add tool_output color to themes

- Added a `tool_output` color to the `Theme` struct.
- Updated all built-in themes to include the new color.
- Modified the TUI to use the `tool_output` color for rendering tool output.

crates/owlen-core/src/provider.rs

@@ -17,7 +17,7 @@ pub type ChatStream = Pin<Box<dyn Stream<Item = Result<ChatResponse>> + Send>>;
 /// use std::sync::Arc;
 /// use futures::Stream;
 /// use owlen_core::provider::{Provider, ProviderRegistry, ChatStream};
-/// use owlen_core::types::{ChatRequest, ChatResponse, ModelInfo, Message};
+/// use owlen_core::types::{ChatRequest, ChatResponse, ModelInfo, Message, Role, ChatParameters};
 /// use owlen_core::Result;
 ///
 /// // 1. Create a mock provider
@@ -31,18 +31,23 @@ pub type ChatStream = Pin<Box<dyn Stream<Item = Result<ChatResponse>> + Send>>;
 ///
 ///     async fn list_models(&self) -> Result<Vec<ModelInfo>> {
 ///         Ok(vec![ModelInfo {
+///             id: "mock-model".to_string(),
 ///             provider: "mock".to_string(),
 ///             name: "mock-model".to_string(),
-///             ..Default::default()
+///             description: None,
+///             context_window: None,
+///             capabilities: vec![],
+///             supports_tools: false,
 ///         }])
 ///     }
 ///
 ///     async fn chat(&self, request: ChatRequest) -> Result<ChatResponse> {
 ///         let content = format!("Response to: {}", request.messages.last().unwrap().content);
 ///         Ok(ChatResponse {
-///             model: request.model,
-///             message: Message { role: "assistant".to_string(), content, ..Default::default() },
-///             ..Default::default()
+///             message: Message::new(Role::Assistant, content),
+///             usage: None,
+///             is_streaming: false,
+///             is_final: true,
 ///         })
 ///     }
 ///
@@ -67,8 +72,9 @@ pub type ChatStream = Pin<Box<dyn Stream<Item = Result<ChatResponse>> + Send>>;
 ///
 ///     let request = ChatRequest {
 ///         model: "mock-model".to_string(),
-///         messages: vec![Message { role: "user".to_string(), content: "Hello".to_string(), ..Default::default() }],
-///         ..Default::default()
+///         messages: vec![Message::new(Role::User, "Hello".to_string())],
+///         parameters: ChatParameters::default(),
+///         tools: None,
 ///     };
 ///
 ///     let response = provider.chat(request).await.unwrap();