feat(proxy): add ProviderType enum for fine-grained provider detection

Introduce ProviderType enum to distinguish between different provider
implementations (Claude, ClaudeAuth, Codex, Gemini, GeminiCli, OpenRouter).
This enables proper authentication handling and request transformation
based on the actual provider type rather than just AppType.

- Add ProviderType enum with detection logic from config
- Enhance Claude adapter with OpenRouter detection
- Enhance Gemini adapter with CLI mode detection
- Add helper methods for provider type inference

src-tauri/src/proxy/response_handler.rs

@@ -0,0 +1,214 @@
+//! Response Handler - 统一响应处理
+//!
+//! 提供流式和非流式响应的统一处理接口
+
+use super::session::ProxySession;
+use super::usage::parser::TokenUsage;
+use super::ProxyError;
+use bytes::Bytes;
+use futures::stream::{Stream, StreamExt};
+use serde_json::Value;
+use std::sync::Arc;
+use std::time::{Duration, Instant};
+use tokio::sync::Mutex;
+use tokio::time::timeout;
+
+/// 响应类型
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[allow(dead_code)]
+pub enum ResponseType {
+    /// 流式响应 (SSE)
+    Stream,
+    /// 非流式响应
+    NonStream,
+}
+
+impl ResponseType {
+    /// 从 Content-Type 检测响应类型
+    #[allow(dead_code)]
+    pub fn from_content_type(content_type: &str) -> Self {
+        if content_type.contains("text/event-stream") {
+            ResponseType::Stream
+        } else {
+            ResponseType::NonStream
+        }
+    }
+}
+
+/// 流式响应处理器
+#[allow(dead_code)]
+pub struct StreamHandler {
+    /// 空闲超时时间
+    idle_timeout: Duration,
+    /// 收集的事件
+    events: Arc<Mutex<Vec<Value>>>,
+}
+
+#[allow(dead_code)]
+impl StreamHandler {
+    /// 创建新的流式处理器
+    pub fn new(idle_timeout_secs: u64) -> Self {
+        Self {
+            idle_timeout: Duration::from_secs(idle_timeout_secs),
+            events: Arc::new(Mutex::new(Vec::new())),
+        }
+    }
+
+    /// 处理流式响应，返回分流后的客户端流
+    ///
+    /// 客户端流立即返回，内部流在后台收集事件
+    pub fn handle_stream<S>(
+        &self,
+        stream: S,
+    ) -> impl Stream<Item = Result<Bytes, std::io::Error>> + Send
+    where
+        S: Stream<Item = Result<Bytes, reqwest::Error>> + Send + 'static,
+    {
+        let events = self.events.clone();
+        let idle_timeout = self.idle_timeout;
+
+        async_stream::stream! {
+            let mut _last_activity = Instant::now();
+            let mut buffer = String::new();
+
+            tokio::pin!(stream);
+
+            loop {
+                let chunk_result = timeout(idle_timeout, stream.next()).await;
+
+                match chunk_result {
+                    Ok(Some(Ok(bytes))) => {
+                        _last_activity = Instant::now();
+
+                        // 解析 SSE 事件
+                        let text = String::from_utf8_lossy(&bytes);
+                        buffer.push_str(&text);
+
+                        // 提取完整事件
+                        while let Some(pos) = buffer.find("\n\n") {
+                            let event_text = buffer[..pos].to_string();
+                            buffer = buffer[pos + 2..].to_string();
+
+                            for line in event_text.lines() {
+                                if let Some(data) = line.strip_prefix("data: ") {
+                                    if data.trim() != "[DONE]" {
+                                        if let Ok(json) = serde_json::from_str::<Value>(data) {
+                                            let mut guard = events.lock().await;
+                                            guard.push(json);
+                                        }
+                                    }
+                                }
+                            }
+                        }
+
+                        yield Ok(bytes);
+                    }
+                    Ok(Some(Err(e))) => {
+                        log::error!("流错误: {e}");
+                        yield Err(std::io::Error::other(e.to_string()));
+                        break;
+                    }
+                    Ok(None) => {
+                        // 流结束
+                        break;
+                    }
+                    Err(_) => {
+                        // 空闲超时
+                        log::warn!("流式响应空闲超时: {idle_timeout:?} 无数据");
+                        yield Err(std::io::Error::other("Stream idle timeout"));
+                        break;
+                    }
+                }
+            }
+        }
+    }
+
+    /// 获取收集的事件
+    pub async fn get_events(&self) -> Vec<Value> {
+        let guard = self.events.lock().await;
+        guard.clone()
+    }
+
+    /// 从收集的事件中提取 Token 使用量
+    pub async fn extract_usage(&self, session: &ProxySession) -> Option<TokenUsage> {
+        let events = self.get_events().await;
+
+        match session.client_format {
+            super::session::ClientFormat::Claude => TokenUsage::from_claude_stream_events(&events),
+            super::session::ClientFormat::Codex => TokenUsage::from_codex_stream_events(&events),
+            super::session::ClientFormat::Gemini | super::session::ClientFormat::GeminiCli => {
+                TokenUsage::from_gemini_stream_chunks(&events)
+            }
+            _ => None,
+        }
+    }
+}
+
+/// 非流式响应处理器
+#[allow(dead_code)]
+pub struct NonStreamHandler;
+
+#[allow(dead_code)]
+impl NonStreamHandler {
+    /// 处理非流式响应
+    ///
+    /// 克隆响应体用于后台解析，原始响应立即返回
+    pub async fn handle_response(
+        body: &[u8],
+        session: &ProxySession,
+    ) -> Result<Option<TokenUsage>, ProxyError> {
+        let json: Value = serde_json::from_slice(body)
+            .map_err(|e| ProxyError::TransformError(format!("Failed to parse response: {e}")))?;
+
+        let usage = match session.client_format {
+            super::session::ClientFormat::Claude => TokenUsage::from_claude_response(&json),
+            super::session::ClientFormat::Codex => TokenUsage::from_codex_response_adjusted(&json),
+            super::session::ClientFormat::Gemini | super::session::ClientFormat::GeminiCli => {
+                TokenUsage::from_gemini_response(&json)
+            }
+            super::session::ClientFormat::OpenAI => TokenUsage::from_openrouter_response(&json),
+            _ => None,
+        };
+
+        Ok(usage)
+    }
+}
+
+/// 统一响应分发器
+#[allow(dead_code)]
+pub struct ResponseDispatcher;
+
+#[allow(dead_code)]
+impl ResponseDispatcher {
+    /// 判断响应类型
+    pub fn detect_type(content_type: &str) -> ResponseType {
+        ResponseType::from_content_type(content_type)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_response_type_detection() {
+        assert_eq!(
+            ResponseType::from_content_type("text/event-stream"),
+            ResponseType::Stream
+        );
+        assert_eq!(
+            ResponseType::from_content_type("text/event-stream; charset=utf-8"),
+            ResponseType::Stream
+        );
+        assert_eq!(
+            ResponseType::from_content_type("application/json"),
+            ResponseType::NonStream
+        );
+    }
+
+    #[test]
+    fn test_stream_handler_creation() {
+        let handler = StreamHandler::new(30);
+        assert_eq!(handler.idle_timeout, Duration::from_secs(30));
+    }
+}