Merge upstream Quorinex/Kiro-Go v1.0.6 with local features preserved

Brought in 9 upstream commits:
- 221348b thinking routing: ClaudeRequest.Thinking + Signature + includeEmptyThinkingBlock
- 0203357 + 31aa6aa accurate input_tokens via contextUsageEvent
- 404e242 + 50f1a7e outbound proxy (socks5/http) + UI
- 940dc78 version bump to 1.0.6
- 3 CI workflow changes

Strategy: took upstream base for the 4 conflicting files, then re-applied
our local changes on top:
- config.go: InvalidModelRetries field + GetInvalidModelRetries/UpdateInvalidModelRetries
- kiro.go: AmazonQ origin CLI->AI_EDITOR, attempt-level retry loop for
  INVALID_MODEL_ID, detailed log.Printf (account/model/attempt/elapsed),
  log import; adopted upstream's kiroHttpStore atomic pointer for Do()
- handler.go: /admin/api/general GET/POST + apiGetGeneralConfig +
  apiUpdateGeneralConfig
- web/index.html: General Settings card (invalid-model-retries),
  CN/EN i18n, loadGeneralConfig/saveGeneralConfig, call from initSettings

Build + full test suite green on Go 1.24.3.

config/config.go

@@ -108,6 +108,12 @@ type Config struct {
 	// Endpoint configuration: "auto", "codewhisperer", or "amazonq"
 	PreferredEndpoint string `json:"preferredEndpoint,omitempty"`
 
+	// Proxy configuration: optional outbound proxy for Kiro API requests
+	// Format: "socks5://host:port", "socks5://user:pass@host:port",
+	//         "http://host:port",  "http://user:pass@host:port"
+	// Leave empty to connect directly.
+	ProxyURL string `json:"proxyURL,omitempty"`
+
 	// General behavior settings
 	InvalidModelRetries int `json:"invalidModelRetries,omitempty"` // Same-endpoint retry count on INVALID_MODEL_ID (default: 3)
 
@@ -140,7 +146,7 @@ type AccountInfo struct {
 }
 
 // Version current version
-const Version = "1.0.5"
+const Version = "1.0.6"
 
 var (
 	cfg     *Config
@@ -448,6 +454,21 @@ func UpdatePreferredEndpoint(endpoint string) error {
 	return Save()
 }
 
+// GetProxyURL 获取出站代理地址
+func GetProxyURL() string {
+	cfgLock.RLock()
+	defer cfgLock.RUnlock()
+	return cfg.ProxyURL
+}
+
+// UpdateProxySettings 更新出站代理配置
+func UpdateProxySettings(proxyURL string) error {
+	cfgLock.Lock()
+	defer cfgLock.Unlock()
+	cfg.ProxyURL = proxyURL
+	return Save()
+}
+
 // GetInvalidModelRetries 返回 INVALID_MODEL_ID 同端点重试次数（默认 3）
 func GetInvalidModelRetries() int {
 	cfgLock.RLock()