fix(mom): private channel messages not being logged

- Add message.groups to required bot events in README
- Add groups:history and groups:read to required scopes in README
- app_mention handler now logs messages directly instead of relying on message event
- Add deduplication in ChannelStore.logMessage() to prevent double-logging
- Remove redundant current message append in agent.ts (already in log)

packages/mom/README.md

@@ -31,6 +31,8 @@ npm install @mariozechner/pi-mom
    - `chat:write`
    - `files:read`
    - `files:write`
+   - `groups:history`
+   - `groups:read`
    - `im:history`
    - `im:read`
    - `im:write`
@@ -38,6 +40,7 @@ npm install @mariozechner/pi-mom
 5. **Subscribe to Bot Events** (Event Subscriptions):
    - `app_mention`
    - `message.channels`
+   - `message.groups`
    - `message.im`
 6. Install the app to your workspace. Get the **Bot User OAuth Token**. This is `MOM_SLACK_BOT_TOKEN`
 7. Add mom to any channels where you want her to operate (she'll only see messages in channels she's added to)