Fix variable substitution patterns: remove :-default fallbacks

- Replace all ${VARIABLE:-default} with ${VARIABLE} in compose files
- Ensure explicit variable requirements without default values
- Updated 10 docker-compose.yml files across all stacks
- Made reset-ondemand-services.sh executable

docker-compose/core/docker-compose.yml

@@ -23,8 +23,8 @@ services:
     container_name: duckdns
     restart: unless-stopped
     environment:
-      - PUID=${PUID:-1000}
-      - PGID=${PGID:-1000}
+      - PUID=${PUID}
+      - PGID=${PGID}
       - TZ=${TZ}
       - SUBDOMAINS=${DUCKDNS_SUBDOMAINS}
       - TOKEN=${DUCKDNS_TOKEN}