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/proxy/resources/nginx/nginx.conf

@@ -0,0 +1,48 @@
+worker_processes  auto;
+
+error_log  /dev/stderr warn;
+pid        /tmp/nginx.pid;
+
+events {
+    worker_connections  1024;
+}
+
+http {
+    proxy_temp_path /tmp/proxy_temp;
+    client_body_temp_path /tmp/client_temp;
+    fastcgi_temp_path /tmp/fastcgi_temp;
+    uwsgi_temp_path /tmp/uwsgi_temp;
+    scgi_temp_path /tmp/scgi_temp;
+
+    client_max_body_size 10M;
+    proxy_buffering off;
+    proxy_request_buffering off;
+
+    include       /etc/nginx/mime.types;
+    default_type  application/octet-stream;
+
+    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
+                      '$status $body_bytes_sent "$http_referer" '
+                      '"$http_user_agent" "$http_x_forwarded_for"';
+
+    access_log  /dev/stdout  main;
+
+    sendfile        on;
+
+    keepalive_timeout  65;
+
+    server {
+        listen       8888;
+        server_name  _;
+        location /health {
+            access_log off;
+            return 200 "OK";
+        }
+    }
+
+    include /etc/nginx/conf.d/*.conf;
+}
+
+stream {
+    include /etc/nginx/streams.d/*.conf;
+}