Add custom error pages and Nginx configuration for proxy module

- Introduced custom HTML error pages for various HTTP status codes (400, 401, 403, 404, 408, 429, 500, 502, 503, 504) in the proxy module.
- Created a .gitignore file to exclude non-HTML files in the error resources directory.
- Updated Nginx configuration to serve custom error pages for upstream errors.
- Added new Nginx configuration templates for handling HTTP and stream protocols.
- Implemented Wireguard configuration templates and associated variables for secure connections.
- Established Kubernetes resources for Stunnel and Wireguard, including deployment, service accounts, and config maps.
- Defined variables for the Stunnel and Wireguard modules to facilitate configuration.
- Created a new Wol Proxy module with Kubernetes resources for deployment and service management.

terraform/modules/utils/stunnel/resources/stunnel.conf.tpl

@@ -0,0 +1,16 @@
+foreground = yes
+
+%{ for target in local_targets ~}
+[server-${target.listen_port}]
+accept = 0.0.0.0:${target.listen_port}
+connect = ${target.target_host}:${target.target_port}
+cert = /etc/ssl/certs/private/tls.crt
+key = /etc/ssl/certs/private/tls.key
+%{ endfor ~}
+
+%{ for target in remote_targets ~}
+[client-${target.listen_port}]
+client = yes
+accept = 0.0.0.0:${target.listen_port}
+connect = ${target.target_host}:${target.target_port}
+%{ endfor ~}