feat(kiro): add AWS Builder ID authentication support

- Add --kiro-aws-login flag for AWS Builder ID device code flow
- Add DoKiroAWSLogin function for AWS SSO OIDC authentication
- Complete Kiro integration with AWS, Google OAuth, and social auth
- Add kiro executor, translator, and SDK components
- Update browser support for Kiro authentication flows

internal/runtime/executor/proxy_helpers.go

@@ -6,6 +6,7 @@ import (
 	"net/http"
 	"net/url"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
@@ -14,11 +15,19 @@ import (
 	"golang.org/x/net/proxy"
 )
 
+// httpClientCache caches HTTP clients by proxy URL to enable connection reuse
+var (
+	httpClientCache      = make(map[string]*http.Client)
+	httpClientCacheMutex sync.RWMutex
+)
+
 // newProxyAwareHTTPClient creates an HTTP client with proper proxy configuration priority:
 // 1. Use auth.ProxyURL if configured (highest priority)
 // 2. Use cfg.ProxyURL if auth proxy is not configured
 // 3. Use RoundTripper from context if neither are configured
 //
+// This function caches HTTP clients by proxy URL to enable TCP/TLS connection reuse.
+//
 // Parameters:
 //   - ctx: The context containing optional RoundTripper
 //   - cfg: The application configuration
@@ -28,11 +37,6 @@ import (
 // Returns:
 //   - *http.Client: An HTTP client with configured proxy or transport
 func newProxyAwareHTTPClient(ctx context.Context, cfg *config.Config, auth *cliproxyauth.Auth, timeout time.Duration) *http.Client {
-	httpClient := &http.Client{}
-	if timeout > 0 {
-		httpClient.Timeout = timeout
-	}
-
 	// Priority 1: Use auth.ProxyURL if configured
 	var proxyURL string
 	if auth != nil {
@@ -44,11 +48,39 @@ func newProxyAwareHTTPClient(ctx context.Context, cfg *config.Config, auth *clip
 		proxyURL = strings.TrimSpace(cfg.ProxyURL)
 	}
 
+	// Build cache key from proxy URL (empty string for no proxy)
+	cacheKey := proxyURL
+
+	// Check cache first
+	httpClientCacheMutex.RLock()
+	if cachedClient, ok := httpClientCache[cacheKey]; ok {
+		httpClientCacheMutex.RUnlock()
+		// Return a wrapper with the requested timeout but shared transport
+		if timeout > 0 {
+			return &http.Client{
+				Transport: cachedClient.Transport,
+				Timeout:   timeout,
+			}
+		}
+		return cachedClient
+	}
+	httpClientCacheMutex.RUnlock()
+
+	// Create new client
+	httpClient := &http.Client{}
+	if timeout > 0 {
+		httpClient.Timeout = timeout
+	}
+
 	// If we have a proxy URL configured, set up the transport
 	if proxyURL != "" {
 		transport := buildProxyTransport(proxyURL)
 		if transport != nil {
 			httpClient.Transport = transport
+			// Cache the client
+			httpClientCacheMutex.Lock()
+			httpClientCache[cacheKey] = httpClient
+			httpClientCacheMutex.Unlock()
 			return httpClient
 		}
 		// If proxy setup failed, log and fall through to context RoundTripper
@@ -60,6 +92,13 @@ func newProxyAwareHTTPClient(ctx context.Context, cfg *config.Config, auth *clip
 		httpClient.Transport = rt
 	}
 
+	// Cache the client for no-proxy case
+	if proxyURL == "" {
+		httpClientCacheMutex.Lock()
+		httpClientCache[cacheKey] = httpClient
+		httpClientCacheMutex.Unlock()
+	}
+
 	return httpClient
 }