feat(messaging): webhook push sync for Gmail, Calendar and Microsoft (#21970)

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packages/twenty-server/src/engine/core-modules/core-engine.module.ts

@@ -47,6 +47,7 @@ import { MessageQueueModule } from 'src/engine/core-modules/message-queue/messag
 import { messageQueueModuleFactory } from 'src/engine/core-modules/message-queue/message-queue.module-factory';
 import { TimelineMessagingModule } from 'src/engine/core-modules/messaging/timeline-messaging.module';
 import { MessagingWebhooksModule } from 'src/modules/messaging-webhooks/messaging-webhooks.module';
+import { ConnectedAccountSyncWebhooksModule } from 'src/modules/connected-account-sync-webhooks/connected-account-sync-webhooks.module';
 import { MetricsModule } from 'src/engine/core-modules/metrics/metrics.module';
 import { MetricsService } from 'src/engine/core-modules/metrics/metrics.service';
 import { OpenApiModule } from 'src/engine/core-modules/open-api/open-api.module';
@@ -88,6 +89,7 @@ import { FileModule } from './file/file.module';
     BillingModule,
     BillingWebhookModule,
     MessagingWebhooksModule,
+    ConnectedAccountSyncWebhooksModule,
     UsageModule,
     ClientConfigModule,
     FeatureFlagModule,

packages/twenty-server/src/engine/core-modules/feature-flag/constants/public-feature-flag.const.ts

@@ -28,6 +28,14 @@ export const PUBLIC_FEATURE_FLAGS: PublicFeatureFlag[] = [
         'Show the per-page hero illustration + video walkthrough modal on settings pages',
     },
   },
+  {
+    key: FeatureFlagKey.IS_MESSAGING_CALENDAR_WEBHOOK_ENABLED,
+    metadata: {
+      label: 'Messaging & Calendar Webhooks',
+      description:
+        'Sync Gmail, Google Calendar, and Microsoft 365 mail/calendar via provider push notifications instead of cron polling',
+    },
+  },
   ...(process.env.CLOUDFLARE_API_KEY
     ? [
         // {

packages/twenty-server/src/engine/core-modules/twenty-config/config-variables.ts

@@ -177,6 +177,29 @@ export class ConfigVariables {
   })
   MESSAGING_PROVIDER_GMAIL_ENABLED = false;
 
+  @ConfigVariablesMetadata({
+    group: ConfigVariablesGroup.GOOGLE_AUTH,
+    isSensitive: false,
+    description:
+      'Google Cloud Pub/Sub topic that Gmail push notifications publish to ' +
+      '(format: projects/<project>/topics/<topic>). Required for webhook-based Gmail sync.',
+    type: ConfigVariableType.STRING,
+  })
+  @IsOptional()
+  MESSAGING_GMAIL_PUBSUB_TOPIC: string;
+
+  @ConfigVariablesMetadata({
+    group: ConfigVariablesGroup.GOOGLE_AUTH,
+    isSensitive: false,
+    description:
+      'Service account email authorized to deliver Gmail Pub/Sub push ' +
+      'notifications. The signed OIDC token on each push is verified against ' +
+      'this email. Required for webhook-based Gmail sync.',
+    type: ConfigVariableType.STRING,
+  })
+  @IsOptional()
+  MESSAGING_GMAIL_PUBSUB_VERIFICATION_EMAIL: string;
+
   @ConfigVariablesMetadata({
     group: ConfigVariablesGroup.ADVANCED_SETTINGS,
     description: 'Enable or disable the IMAP messaging integration',