feat(proxy): update failover timeout and circuit breaker defaults (#521)

- Double all timeout values (streaming/non-streaming)
- Codex/Gemini: circuit_failure_threshold 5→4, error_rate 0.5→0.6
- Claude: circuit_error_rate_threshold 0.6→0.7

src-tauri/src/proxy/circuit_breaker.rs

@@ -49,10 +49,10 @@ pub struct CircuitBreakerConfig {
 impl Default for CircuitBreakerConfig {
     fn default() -> Self {
         Self {
-            failure_threshold: 5,
+            failure_threshold: 4,
             success_threshold: 2,
             timeout_seconds: 60,
-            error_rate_threshold: 0.5,
+            error_rate_threshold: 0.6,
             min_requests: 10,
         }
     }

src-tauri/src/proxy/types.rs

@@ -28,11 +28,11 @@ pub struct ProxyConfig {
 }
 
 fn default_streaming_first_byte_timeout() -> u64 {
-    30
+    60
 }
 
 fn default_streaming_idle_timeout() -> u64 {
-    60
+    120
 }
 
 fn default_non_streaming_timeout() -> u64 {
@@ -45,11 +45,11 @@ impl Default for ProxyConfig {
             listen_address: "127.0.0.1".to_string(),
             listen_port: 15721, // 使用较少占用的高位端口
             max_retries: 3,
-            request_timeout: 300,
+            request_timeout: 600,
             enable_logging: true,
             live_takeover_active: false,
-            streaming_first_byte_timeout: 30,
-            streaming_idle_timeout: 60,
+            streaming_first_byte_timeout: 60,
+            streaming_idle_timeout: 120,
             non_streaming_timeout: 600,
         }
     }