feat: add dockcheck update labels and fix Gotify service names

- Add mag37.dockcheck.update labels to audiobookshelf, caddy, gitea services
- Fix Gotify container names in Caddyfile routing
- Add explicit container names for gotify and igotify-assistant services
- Update Authentik to version 2025.6.3
- Fix environment variable format in gotify-compose template

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

roles/docker/templates/gotify-compose.yml.j2

@@ -1,6 +1,7 @@
 services:
   gotify:
     image: gotify/server:latest
+    container_name: gotify
     restart: unless-stopped
     volumes:
       - gotify_data:/app/data
@@ -19,10 +20,11 @@ services:
   igotify-assistant:
     image: ghcr.io/androidseb25/igotify-notification-assist:latest
     restart: unless-stopped
+    container_name: igotify-assistant
     volumes:
       - igotify_data:/app/data
     environment:
-      - TZ=America/Denver
+      TZ: America/Denver
     depends_on:
       - gotify
     labels: