[SILO-463] chore: add privacy policy section for slack for marketplace listing

Author: Prashant-Surya

docs/integrations/slack.mdx

@@ -175,6 +175,17 @@ With link previews, you can interact with the work item directly from Slack.
 
 This makes it easy to stay updated and take action without leaving Slack.
 
+## Privacy and data handling
+
+When you use the Slack integration with Plane, we take your privacy seriously. The integration only accesses the minimum permissions necessary to function properly, and we handle your data in accordance with our [Privacy Policy](https://plane.so/legals/privacy-policy).
+
+The integration may collect and process:
+- Messages and threads you choose to sync with Plane work items
+- Channel information for project notifications
+- Basic user information for authentication and personalization
+
+All data is encrypted in transit and at rest, and you can disconnect the integration at any time from your [Workspace Settings](/core-concepts/workspaces/overview#workspace-settings) or [Profile settings](/core-concepts/account/settings).
+
 ---
 
 By using these features, you can reduce context-switching and manage Plane work items directly from Slack—keeping your workflow smooth and efficient.