feat: add SMS verification registration with UniSMS provider

- Add phone field to user model with index and helper methods
- Implement SMS provider interface with UniSMS (合一短信) implementation
- Add SMS verification code sending endpoint with rate limiting (1/60s)
- Support SMS registration in Register() (mutually exclusive with email)
- Add SMS configuration to admin settings (provider, keys, signature, template)
- Display phone number in admin user list contact column
- Add i18n translations for all SMS-related messages (zh-CN, en, zh-TW)
- Add Claude Code skills: sync-upstream, migrate-server
- Update CLAUDE.md with git conventions and deployment guide

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

model/option.go

@@ -62,6 +62,12 @@ func InitOptionMap() {
 	common.OptionMap["SMTPAccount"] = ""
 	common.OptionMap["SMTPToken"] = ""
 	common.OptionMap["SMTPSSLEnabled"] = strconv.FormatBool(common.SMTPSSLEnabled)
+	common.OptionMap["SMSVerificationEnabled"] = strconv.FormatBool(common.SMSVerificationEnabled)
+	common.OptionMap["SMSProvider"] = common.SMSProvider
+	common.OptionMap["SMSAccessKeyId"] = common.SMSAccessKeyId
+	common.OptionMap["SMSAccessKeySecret"] = common.SMSAccessKeySecret
+	common.OptionMap["SMSSignName"] = common.SMSSignName
+	common.OptionMap["SMSTemplateCode"] = common.SMSTemplateCode
 	common.OptionMap["Notice"] = ""
 	common.OptionMap["About"] = ""
 	common.OptionMap["HomePageContent"] = ""
@@ -292,6 +298,8 @@ func updateOptionMap(key string, value string) (err error) {
 			setting.StopOnSensitiveEnabled = boolValue
 		case "SMTPSSLEnabled":
 			common.SMTPSSLEnabled = boolValue
+		case "SMSVerificationEnabled":
+			common.SMSVerificationEnabled = boolValue
 		case "WorkerAllowHttpImageRequestEnabled":
 			system_setting.WorkerAllowHttpImageRequestEnabled = boolValue
 		case "DefaultUseAutoGroup":
@@ -314,6 +322,16 @@ func updateOptionMap(key string, value string) (err error) {
 		common.SMTPFrom = value
 	case "SMTPToken":
 		common.SMTPToken = value
+	case "SMSProvider":
+		common.SMSProvider = value
+	case "SMSAccessKeyId":
+		common.SMSAccessKeyId = value
+	case "SMSAccessKeySecret":
+		common.SMSAccessKeySecret = value
+	case "SMSSignName":
+		common.SMSSignName = value
+	case "SMSTemplateCode":
+		common.SMSTemplateCode = value
 	case "ServerAddress":
 		system_setting.ServerAddress = value
 	case "WorkerUrl":