refactor(core): 扫清 v0.1 Phase A 技术债

- 修复测试编译回归：补全 session.rs/cycle.rs 测试模块导入；
convert.rs 2 处 irrefutable if let 改为 let
- composer.rs 迁移至 IR：OpenaiChatMessage → Message，
ContentField/OpenaiContentPart → ContentBlock；删除 set_message_name
和 build_request；developer 消息映射为 Message::System
- knowledge.rs 锁修复：std::sync::Mutex → tokio::sync::Mutex；
search() 优化锁粒度（锁内仅 clone IDs，避免锁内异步 IO）
- 标记 ChatResponse / ToolDefinition 为废弃（#[deprecated(since = "0.1.0")]），
内部使用点加 #[allow(deprecated)] 抑制警告
- clippy 清零：合并冗余 if、手动 strip_prefix 改 strip_prefix、
多处 dead_code 抑制、测试代码清理

src/llm/cycle.rs

@@ -21,6 +21,7 @@ use crate::llm::stream::StreamEvent;
 use crate::llm::types::message::{ContentBlock, Message};
 use crate::llm::types::request_v2::MessageRequest;
 use crate::llm::types::response_v2::{MessageResponse, StopReason};
+#[allow(deprecated)]
 use crate::llm::types::{ToolChoice, ToolDefinition};
 
 /// LLM 调用周期配置。
@@ -79,6 +80,7 @@ pub struct LlmCycle {
     compact_state: CompactState,
 }
 
+#[allow(deprecated)]
 impl LlmCycle {
     /// 创建一个新的 LlmCycle（持有 `Box<dyn LlmProvider>` 的独占所有权）。
     ///
@@ -175,13 +177,10 @@ impl LlmCycle {
         messages: Vec<Message>,
         tools: Vec<ToolDefinition>,
     ) -> Result<MessageResponse, LlmError> {
-        let ir_messages: Vec<Message> = messages;
-        let ir_tools: Vec<ToolDefinition> = tools.clone();
-
         let request = MessageRequest {
             model: self.config.model.clone(),
-            messages: ir_messages,
-            tools: ir_tools,
+            messages,
+            tools,
             tool_choice: ToolChoice::Auto,
             max_tokens: self.config.max_tokens,
             temperature: self.config.temperature,
@@ -672,6 +671,7 @@ fn truncate_tool_result(s: &str, max_bytes: usize) -> String {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::llm::provider::{ProviderCapabilities, ProviderFeatures};
     use crate::tools::{BaseTool, ToolRegistry};
     use async_trait::async_trait;
     use futures_core::Stream;
@@ -858,8 +858,10 @@ mod tests {
 
     #[tokio::test]
     async fn test_submit_with_tools_max_turns_exceeded() {
-        let mut config = CycleConfig::default();
-        config.max_tool_turns = Some(2);
+        let config = CycleConfig {
+            max_tool_turns: Some(2),
+            ..Default::default()
+        };
         let responses = vec![
             assistant_tool_call_response(vec![("c1", "add", r#"{"a":1,"b":1}"#)]),
             assistant_tool_call_response(vec![("c2", "add", r#"{"a":1,"b":1}"#)]),