Feature/error request logging (#401)

* feat(proxy): add error mapper for HTTP status code mapping

- Add error_mapper.rs module to map ProxyError to HTTP status codes
- Implement map_proxy_error_to_status() for error classification
- Implement get_error_message() for user-friendly error messages
- Support all error types: upstream, timeout, connection, provider failures
- Include comprehensive unit tests for all mappings

* feat(proxy): enhance error logging with context support

- Add log_error_with_context() method for detailed error recording
- Support streaming flag, session_id, and provider_type fields
- Remove dead_code warning from log_error() method
- Enable comprehensive error request tracking in database

* feat(proxy): implement error capture and logging in all handlers

- Capture and log all failed requests in handle_messages (Claude)
- Capture and log all failed requests in handle_gemini (Gemini)
- Capture and log all failed requests in handle_responses (Codex)
- Capture and log all failed requests in handle_chat_completions (Codex)
- Record error status codes, messages, and latency for all failures
- Generate unique session_id for each request
- Support both streaming and non-streaming error scenarios

* style: fix clippy warnings and typescript errors

- Add allow(dead_code) for CircuitBreaker::get_state (reserved for future)
- Fix all uninlined format string warnings (27 instances)
- Use inline format syntax for better readability
- Fix unused import and parameter warnings in ProviderActions.tsx
- Achieve zero warnings in both Rust and TypeScript

* style: apply code formatting

- Remove trailing whitespace in misc.rs
- Add trailing comma in App.tsx
- Format multi-line className in ProviderCard.tsx

* feat(proxy): add settings button to proxy panel

Add configuration buttons in both running and stopped states to
provide easy access to proxy settings dialog.

* fix(speedtest): skip client build for invalid inputs

* chore(clippy): fix uninlined format args

* Merge branch 'main' into feature/error-request-logging

src-tauri/src/proxy/usage/logger.rs

@@ -107,6 +107,8 @@ impl<'a> UsageLogger<'a> {
     }
 
     /// 记录失败的请求
+    ///
+    /// 用于记录无法从上游获取 usage 信息的失败请求
     #[allow(dead_code, clippy::too_many_arguments)]
     pub fn log_error(
         &self,
@@ -138,6 +140,43 @@ impl<'a> UsageLogger<'a> {
         self.log_request(&log)
     }
 
+    /// 记录失败的请求（带更多上下文信息）
+    ///
+    /// 相比 log_error，这个方法接受更多参数以提供完整的请求上下文
+    #[allow(clippy::too_many_arguments)]
+    pub fn log_error_with_context(
+        &self,
+        request_id: String,
+        provider_id: String,
+        app_type: String,
+        model: String,
+        status_code: u16,
+        error_message: String,
+        latency_ms: u64,
+        is_streaming: bool,
+        session_id: Option<String>,
+        provider_type: Option<String>,
+    ) -> Result<(), AppError> {
+        let log = RequestLog {
+            request_id,
+            provider_id,
+            app_type,
+            model,
+            usage: TokenUsage::default(),
+            cost: None,
+            latency_ms,
+            first_token_ms: None,
+            status_code,
+            error_message: Some(error_message),
+            session_id,
+            provider_type,
+            is_streaming,
+            cost_multiplier: "1.0".to_string(),
+        };
+
+        self.log_request(&log)
+    }
+
     /// 获取模型定价
     pub fn get_model_pricing(&self, model_id: &str) -> Result<Option<ModelPricing>, AppError> {
         let conn = crate::database::lock_conn!(self.db.conn);