Document credential separation: Nextcloud Mail uses different IMAP/SMTP credentials

CREDENTIALS.md

@@ -10,10 +10,22 @@
 - API Key: Not provided
 - Status: Not provided yet
 
-**Nextcloud System** (current priority):
+## Credentials Provided
+
+### Nextcloud System** (current priority):
 - Server URL: `https://teamworkapps.com`
 - Username: `wltbagent@shortcutsolutions.net`
 - API Key: `1b8a28ca2fc26820fee3f9a8524c351b`
+- **Purpose**: REST API, WebDAV, CalDAV, CardDAV, OCS API endpoints
+
+### Nextcloud Email Integration** (different credentials):
+- **Authentication Method**: IMAP and SMTP (standard mail protocols)
+- **Credentials Available**:
+  - Hostnames (IMAP server, SMTP server)
+  - Username
+  - Password
+- **Purpose**: Email reading/sending via nextcloud-mail integration
+- **Note**: These are separate credentials from the Nextcloud API credentials above
 
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