Fix HTTPS configuration: use service hostname for networking and add HTTP-only compose file

- Updated service name from 'digiserver' to 'digiserver-app' in docker-compose.yml for proper Docker network DNS resolution
- Fixed Caddyfile to reference correct service hostname 'digiserver-app:5000'
- Changed port mapping from 'ports' to 'expose' for internal-only access
- Added docker-compose.http.yml for HTTP-only deployment on port 80 (development/testing)
- Both Flask app and Caddy now communicate correctly over internal Docker network
- App now accessible at https://localhost or https://your-domain.com on port 443

Caddyfile

@@ -9,7 +9,7 @@
     # Automatic HTTPS (Caddy handles Let's Encrypt automatically)
     
     # Reverse proxy to Flask app
-    reverse_proxy digiserver:5000 {
+    reverse_proxy digiserver-app:5000 {
         header_up Host {host}
         header_up X-Real-IP {remote_host}
         header_up X-Forwarded-For {remote_host}
@@ -44,7 +44,7 @@
 # Handle IP address access without automatic HTTPS
 http://192.168.0.206 {
     # Reverse proxy to Flask app
-    reverse_proxy digiserver:5000 {
+    reverse_proxy digiserver-app:5000 {
         # Headers
         header_up Host {host}
         header_up X-Real-IP {remote_host}