fix: hardcode Traefik port labels (Gotcha 6 - vars not expanded in labels)

Coolify does not expand ${VAR} in label values. All loadbalancer port
labels must use hardcoded values:
- trilium:   ${TRILIUM_HTTP_PORT}  → 8080
- adguard:   ${ADGUARD_HTTP_PORT}  → 80
- authentik: ${AUTHENTIK_HTTP_PORT} → 9000
- gitea:     ${GITEA_HTTP_PORT}    → 3000
- wireguard: ${WG_UI_PORT}         → 51821

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

wireguard/docker-compose.yml

@@ -38,7 +38,7 @@ services:
       - proxy
 
     labels:
-      traefik.http.services.wg.loadbalancer.server.port: "${WG_UI_PORT}"
+      traefik.http.services.wg.loadbalancer.server.port: "51821"
 
 networks:
   proxy:

wireguard/stack.env

@@ -2,7 +2,7 @@
 WG_EASY_IMAGE=
 WG_HOST=
 WG_PORT=
-WG_UI_PORT=
+WG_UI_PORT=51821
 
 INIT_ENABLED=
 INIT_USERNAME=