feat: add user token secret management for channels

- Implemented user token secret generation and retrieval in channel service.
- Added ResetUserTokenSecret method to reset the user token secret for channels.
- Updated channel configuration parsing to include user token secret.
- Enhanced WebSocket service to utilize user token secret for external info retrieval.
- Modified dashboard channel edit component to support user token secret display and reset functionality.
- Introduced API endpoint for resetting user token secret.
- Updated IM and SDK configurations to include user token.
- Added tests for user token verification logic.

internal/pkg/enums/external_identity.go

@@ -27,7 +27,7 @@ func GetExternalSourceLabel(v ExternalSource) string {
 // IsAllowedOpenImExternalSource 开放 IM 入口允许的外部来源（闭集校验）。
 func IsAllowedOpenImExternalSource(s ExternalSource) bool {
 	switch s {
-	case ExternalSourceGuest:
+	case ExternalSourceGuest, ExternalSourceUser:
 		return true
 	default:
 		return false