Enhance welcome module with embed text rendering and autorole management

- Updated the welcome embed functionality to allow for user mentions in titles, authors, and footers, while maintaining clickable mentions in descriptions.
- Implemented autorole assignment logic with checks for role manageability and hierarchy, including detailed logging for skipped roles.
- Improved the WebUI to display real user and guild data in the welcome embed preview, enhancing user experience.
- Refactored the welcome text rendering to support additional options for mention handling based on the context of the embed fields.

docs/PHASE-TRACKING.md

@@ -290,6 +290,22 @@
 - [ ] Original löschen/editieren → Starboard aktualisiert/entfernt
 - [ ] Dashboard: aktivieren ohne Kanal → Fehler
 
+## Post-Phase – Welcome Embed Mentions + Autorole + Preview (Status: implementiert)
+
+### Abgeschlossen (Code)
+
+- Embed `{user}` in Titel/Author/Footer als Displayname (Discord resolved Mentions dort nicht)
+- Beschreibung/Content behalten `<@id>`-Mentions
+- Autorole: Rollen nachladen, managed/@everyone filtern, `editable`-Check, Warn-Logs bei Hierarchy/Permission
+- WebUI Embed-/Components-Vorschau: echte Session-User- + Guild-Daten statt Dummy `@Alex`
+
+### Manuell testen
+
+- [ ] Welcome-Embed Titel `Welcome {user}` → Anzeigename, nicht `<@id>`
+- [ ] Beschreibung `{user}` → klickbare Mention
+- [ ] User-Autorollen gesetzt, Bot-Rolle über Autorolle, Manage Roles → Rolle bei Join
+- [ ] Dashboard Welcome-Embed-Vorschau zeigt eigenen Namen/Avatar und Servername/-icon
+
 ## Post-Phase – Automod/Moderation Dashboard Ausbau (Status: implementiert)
 
 ### Abgeschlossen (Code)