fix(ci): carry dual bridge intent through stable parameters

Jenkinsfile

@@ -229,6 +229,14 @@ pipeline {
                         String service = selectedService
                         branches[service] = {
                             String jobName = "${env.RESOLVED_JOB_PREFIX}${service}"
+                            boolean deployBothBridges = service == 'event-bridge-service'
+                                && ['BOTH', 'SELECT'].contains(params.EVENT_BRIDGE_REGION)
+                            String downstreamImageTag = deployBothBridges
+                                ? "${env.IMAGE_TAG}-both"
+                                : env.IMAGE_TAG
+                            String downstreamBridgeRegion = deployBothBridges
+                                ? 'CN'
+                                : params.EVENT_BRIDGE_REGION
                             echo "触发单服务 Job: ${jobName}"
                             def downstreamBuild = build(
                                 job: jobName,
@@ -236,17 +244,16 @@ pipeline {
                                 propagate: false,
                                 parameters: [
                                     string(name: 'SOURCE_COMMIT', value: env.SOURCE_COMMIT),
-                                    string(name: 'IMAGE_TAG', value: env.IMAGE_TAG),
+                                    string(name: 'IMAGE_TAG', value: downstreamImageTag),
                                     string(name: 'ENVIRONMENT', value: env.RESOLVED_ENVIRONMENT),
                                     booleanParam(name: 'DEPLOY', value: params.DEPLOY),
                                     // 总控已完成统一测试，或用户已明确选择跳过；下游仅负责编译、打包和部署。
                                     booleanParam(name: 'SKIP_TESTS', value: true),
                                     string(name: 'IMAGE_REPOSITORY', value: env.RESOLVED_IMAGE_REPOSITORY),
                                     string(name: 'DOCKER_BASE_IMAGE', value: params.DOCKER_BASE_IMAGE),
-                                    // 旧下游 Job 的 ChoiceParameterDefinition 尚不接受 BOTH；
-                                    // 使用兼容值 SELECT 传递，下游新流水线会将其解释为双区域部署。
-                                    string(name: 'EVENT_BRIDGE_REGION', value:
-                                        params.EVENT_BRIDGE_REGION == 'BOTH' ? 'SELECT' : params.EVENT_BRIDGE_REGION)
+                                    // Choice 参数始终传递所有新旧 Job 都接受的单区值；
+                                    // 双区意图通过现有 IMAGE_TAG 参数携带，由下游还原真实镜像标签。
+                                    string(name: 'EVENT_BRIDGE_REGION', value: downstreamBridgeRegion)
                                 ]
                             )
                             downstreamResults[service] = downstreamBuild.result ?: 'UNKNOWN'