docs: document Slack 👀 ack reaction and new scope

Author: mintlify[bot]

references/integrations/slack-integration.mdx

@@ -137,6 +137,8 @@ The Slack integration is also used by AI analyst agents to chat with your data a
 
 To trigger AI responses, mention the Lightdash app in your message. There's only one Lightdash Slack app name to mention - you don't need to specify a particular agent. Lightdash automatically routes your question to the most appropriate agent. If it's unclear which agent should respond, you'll be prompted to choose.
 
+When the bot sees your @mention, it adds an :eyes: reaction to your message to confirm receipt before it starts replying. If the reaction doesn't appear, your Slack workspace likely needs to re-authorize the Lightdash app to grant the new `reactions:write` scope — open your Slack integration settings in Lightdash and reconnect. The bot still responds without the reaction; only the visual acknowledgement is skipped.
+
 <Note>
 By default, all Slack AI agent conversations are attributed to the user who installed the Slack app. To have conversations attributed to individual Slack users (and respect their data permissions), enable the **AI Agents OAuth requirement** in your [Slack integration settings](#ai-agents-configuration).
 </Note>

self-host/customize-deployment/configure-a-slack-app-for-lightdash.mdx

@@ -58,6 +58,7 @@ oauth_config:
       - groups:history
       - links:read
       - links:write
+      - reactions:write
       - users:read
       - im:write
 settings: