fix(copilot): 修复 GitHub Copilot 认证和代理问题 (#1854)

* fix(copilot): 修复 GitHub Copilot 400 认证错误

问题：使用 GitHub Copilot provider 时报错 400 bad request

根因：与 copilot-api 项目对比发现多处差异

修复内容：
- 更新版本号 0.26.7 到 0.38.2
- 更新 API 版本 2025-04-01 到 2025-10-01
- 添加缺失的关键 headers
- 修正 openai-intent 值
- 添加动态 API endpoint 支持
- 同步更新 stream_check.rs headers

Closes #1777

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix: flush stream after write_all in hyper_client proxy

Add explicit flush() calls after write_all() for TLS stream, plain TCP
stream, and CONNECT tunnel requests to ensure buffered data is sent
immediately, preventing connection hangs in Copilot auth header flow.

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

* 修复登录时的剪切板在mac与linux端可能没复制验证码

* fix: flush stream after write_all in hyper_client proxy

Add explicit flush() calls after write_all() for TLS stream, plain TCP
stream, and CONNECT tunnel requests to ensure buffered data is sent
immediately, preventing connection hangs in Copilot auth header flow.

* 修复登录时的剪切板在mac与linux端可能没复制验证码

* 1、修复不同类型的个人商业等不同类型的copilot账号问题
2、将验证码复制改为异步操作

* fix: address PR review comments for Copilot auth                                                      │
│                                                                                                                      │
│ - Fix clipboard blocking by using spawn_blocking for arboard ops                                                     │
│ - Implement dynamic endpoint routing for enterprise Copilot users                                                    │
│ - Add api_endpoints cache cleanup in remove_account() and clear_auth()                                               │
│ - Change API endpoint log level from info to debug                                                                   │
│ - Fix clear_auth() to continue cleanup even if file deletion fails                                                   │
│ - Add 9 unit tests for Copilot detection and api_endpoints cachin

* style: fix cargo fmt formatting

* Fix Copilot dynamic endpoint handling

* fix: restore clear_auth() memory-first cleanup order and fix cache leaks

- Restore clear_auth() to clean memory state before deleting the storage
  file. The previous order (file deletion first) caused a regression where
  users could get stuck in a "cannot log out" state if file removal failed.

- Add missing copilot_models.clear() in clear_auth() — this cache was
  cleaned in remove_account() but never in the full clear path.

- Add endpoint_locks cleanup in both remove_account() and clear_auth()
  to prevent minor in-process memory leaks.

- Update test to assert the correct behavior: memory should be cleaned
  even when file deletion fails.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: 周梦泽 <mengze.zhou@dafeng-tech.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Jason <farion1231@gmail.com>

src-tauri/src/proxy/hyper_client.rs

@@ -359,6 +359,10 @@ async fn send_raw_request(
             .write_all(&raw)
             .await
             .map_err(|e| ProxyError::ForwardFailed(format!("Write failed: {e}")))?;
+        tls_stream
+            .flush()
+            .await
+            .map_err(|e| ProxyError::ForwardFailed(format!("Flush failed: {e}")))?;
 
         let filtered = WriteFilter::new(tls_stream);
         do_hyper_response(filtered, method.clone()).await
@@ -368,6 +372,10 @@ async fn send_raw_request(
             .write_all(&raw)
             .await
             .map_err(|e| ProxyError::ForwardFailed(format!("Write failed: {e}")))?;
+        stream
+            .flush()
+            .await
+            .map_err(|e| ProxyError::ForwardFailed(format!("Flush failed: {e}")))?;
 
         let filtered = WriteFilter::new(stream);
         do_hyper_response(filtered, method.clone()).await
@@ -441,6 +449,10 @@ async fn connect_via_proxy(
         .write_all(connect_req.as_bytes())
         .await
         .map_err(|e| ProxyError::ForwardFailed(format!("CONNECT write failed: {e}")))?;
+    stream
+        .flush()
+        .await
+        .map_err(|e| ProxyError::ForwardFailed(format!("CONNECT flush failed: {e}")))?;
 
     // Read the proxy's response status line
     let mut reader = BufReader::new(&mut stream);