feat(acceptance): 建立同构验收与弹性容量体系

实现本地三节点 K3s 同构环境、脱敏生产快照、Gemini 图片和多参考图视频协议模拟、统一验收报告及故障注入。\n\n新增 Worker 容量控制器、资源与连接预算、任务恢复保护，并将生产验收拆分为 validation 执行和人工 CAS 放量。\n\n验证包括 Go 全量测试、PostgreSQL HTTP 集成测试、go vet、OpenAPI、ShellCheck、前端检查、迁移及发布脚本测试。

apps/api/internal/identity/configuration.go

@@ -163,7 +163,13 @@ func ApplyManifest(revision Revision, input ManifestApplication) (Revision, erro
 	revision.SchemaVersion = input.Manifest.SchemaVersion
 	revision.Issuer = strings.TrimRight(input.Manifest.Issuer, "/")
 	revision.TenantID = input.Manifest.TenantID
-	revision.TenantMode = input.Manifest.TenantMode
+	if input.Manifest.SchemaVersion == 1 {
+		// Manifest V1 intentionally omits tenant_mode on the wire, but the
+		// persisted revision uses the explicit single-tenant discriminator.
+		revision.TenantMode = "single_tenant"
+	} else {
+		revision.TenantMode = input.Manifest.TenantMode
+	}
 	revision.ApplicationID = input.Manifest.ApplicationID
 	revision.Audience = input.Manifest.Audience
 	revision.Scopes = append([]string(nil), input.Manifest.Scopes...)