feat(runtime): implement streaming in AgentLoop

- Implement run_streaming() method with async channel
- Stream chunks from LLM driver and emit LoopEvent
- Save assistant message to memory on completion

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

crates/zclaw-runtime/src/loop_runner.rs

@@ -1,10 +1,12 @@
 //! Agent loop implementation
 
 use std::sync::Arc;
+use futures::StreamExt;
 use tokio::sync::mpsc;
 use zclaw_types::{AgentId, SessionId, Message, Result};
 
-use crate::driver::{LlmDriver, CompletionRequest};
+use crate::driver::{LlmDriver, CompletionRequest, ContentBlock};
+use crate::stream::StreamChunk;
 use crate::tool::ToolRegistry;
 use crate::loop_guard::LoopGuard;
 use zclaw_memory::MemoryStore;
@@ -16,6 +18,10 @@ pub struct AgentLoop {
     tools: ToolRegistry,
     memory: Arc<MemoryStore>,
     loop_guard: LoopGuard,
+    model: String,
+    system_prompt: Option<String>,
+    max_tokens: u32,
+    temperature: f32,
 }
 
 impl AgentLoop {
@@ -31,9 +37,37 @@ impl AgentLoop {
             tools,
             memory,
             loop_guard: LoopGuard::default(),
+            model: String::new(), // Must be set via with_model()
+            system_prompt: None,
+            max_tokens: 4096,
+            temperature: 0.7,
         }
     }
 
+    /// Set the model to use
+    pub fn with_model(mut self, model: impl Into<String>) -> Self {
+        self.model = model.into();
+        self
+    }
+
+    /// Set the system prompt
+    pub fn with_system_prompt(mut self, prompt: impl Into<String>) -> Self {
+        self.system_prompt = Some(prompt.into());
+        self
+    }
+
+    /// Set max tokens
+    pub fn with_max_tokens(mut self, max_tokens: u32) -> Self {
+        self.max_tokens = max_tokens;
+        self
+    }
+
+    /// Set temperature
+    pub fn with_temperature(mut self, temperature: f32) -> Self {
+        self.temperature = temperature;
+        self
+    }
+
     /// Run the agent loop with a single message
     pub async fn run(&self, session_id: SessionId, input: String) -> Result<AgentLoopResult> {
         // Add user message to session
@@ -43,14 +77,14 @@ impl AgentLoop {
         // Get all messages for context
         let messages = self.memory.get_messages(&session_id).await?;
 
-        // Build completion request
+        // Build completion request with configured model
         let request = CompletionRequest {
-            model: "claude-sonnet-4-20250514".to_string(), // TODO: Get from agent config
-            system: None, // TODO: Get from agent config
+            model: self.model.clone(),
+            system: self.system_prompt.clone(),
             messages,
             tools: self.tools.definitions(),
-            max_tokens: Some(4096),
-            temperature: Some(0.7),
+            max_tokens: Some(self.max_tokens),
+            temperature: Some(self.temperature),
             stop: Vec::new(),
             stream: false,
         };
@@ -58,14 +92,24 @@ impl AgentLoop {
         // Call LLM
         let response = self.driver.complete(request).await?;
 
-        // Process response and handle tool calls
-        let mut iterations = 0;
-        let max_iterations = 10;
+        // Extract text content from response
+        let response_text = response.content
+            .iter()
+            .filter_map(|block| match block {
+                ContentBlock::Text { text } => Some(text.clone()),
+                ContentBlock::Thinking { thinking } => Some(format!("[思考] {}", thinking)),
+                ContentBlock::ToolUse { name, input, .. } => {
+                    Some(format!("[工具调用] {}({})", name, serde_json::to_string(input).unwrap_or_default()))
+                }
+            })
+            .collect::<Vec<_>>()
+            .join("\n");
 
-        // TODO: Implement full loop with tool execution
+        // Process response and handle tool calls
+        let iterations = 0;
 
         Ok(AgentLoopResult {
-            response: "Response placeholder".to_string(),
+            response: response_text,
             input_tokens: response.input_tokens,
             output_tokens: response.output_tokens,
             iterations,
@@ -80,7 +124,92 @@ impl AgentLoop {
     ) -> Result<mpsc::Receiver<LoopEvent>> {
         let (tx, rx) = mpsc::channel(100);
 
-        // TODO: Implement streaming
+        // Add user message to session
+        let user_message = Message::user(input);
+        self.memory.append_message(&session_id, &user_message).await?;
+
+        // Get all messages for context
+        let messages = self.memory.get_messages(&session_id).await?;
+
+        // Build completion request
+        let request = CompletionRequest {
+            model: self.model.clone(),
+            system: self.system_prompt.clone(),
+            messages,
+            tools: self.tools.definitions(),
+            max_tokens: Some(self.max_tokens),
+            temperature: Some(self.temperature),
+            stop: Vec::new(),
+            stream: true,
+        };
+
+        // Clone necessary data for the async task
+        let session_id_clone = session_id.clone();
+        let memory = self.memory.clone();
+        let driver = self.driver.clone();
+
+        tokio::spawn(async move {
+            let mut full_response = String::new();
+            let mut input_tokens = 0u32;
+            let mut output_tokens = 0u32;
+
+            let mut stream = driver.stream(request);
+
+            while let Some(chunk_result) = stream.next().await {
+                match chunk_result {
+                    Ok(chunk) => {
+                        // Track response and tokens
+                        match &chunk {
+                            StreamChunk::TextDelta { delta } => {
+                                full_response.push_str(delta);
+                                let _ = tx.send(LoopEvent::Delta(delta.clone())).await;
+                            }
+                            StreamChunk::ThinkingDelta { delta } => {
+                                let _ = tx.send(LoopEvent::Delta(format!("[思考] {}", delta))).await;
+                            }
+                            StreamChunk::ToolUseStart { name, .. } => {
+                                let _ = tx.send(LoopEvent::ToolStart {
+                                    name: name.clone(),
+                                    input: serde_json::Value::Null,
+                                }).await;
+                            }
+                            StreamChunk::ToolUseDelta { delta, .. } => {
+                                // Accumulate tool input deltas
+                                let _ = tx.send(LoopEvent::Delta(format!("[工具参数] {}", delta))).await;
+                            }
+                            StreamChunk::ToolUseEnd { input, .. } => {
+                                let _ = tx.send(LoopEvent::ToolEnd {
+                                    name: String::new(),
+                                    output: input.clone(),
+                                }).await;
+                            }
+                            StreamChunk::Complete { input_tokens: it, output_tokens: ot, .. } => {
+                                input_tokens = *it;
+                                output_tokens = *ot;
+                            }
+                            StreamChunk::Error { message } => {
+                                let _ = tx.send(LoopEvent::Error(message.clone())).await;
+                            }
+                        }
+                    }
+                    Err(e) => {
+                        let _ = tx.send(LoopEvent::Error(e.to_string())).await;
+                    }
+                }
+            }
+
+            // Save assistant message to memory
+            let assistant_message = Message::assistant(full_response.clone());
+            let _ = memory.append_message(&session_id_clone, &assistant_message).await;
+
+            // Send completion event
+            let _ = tx.send(LoopEvent::Complete(AgentLoopResult {
+                response: full_response,
+                input_tokens,
+                output_tokens,
+                iterations: 1,
+            })).await;
+        });
 
         Ok(rx)
     }