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/variables.tf

@@ -0,0 +1,55 @@
+variable "stunnel_version" {
+  description = "Stunnel image version"
+  type        = string
+  default     = "latest"
+}
+
+variable "wireguard_version" {
+  description = "Wireguard image version"
+  type        = string
+  default     = "1.0.20210914-r4-ls54"
+}
+
+variable "issuer_name" {
+  description = "The name of the issuer to use for TLS certificates, internal certificates"
+  type        = string
+  default     = "internal-ca"
+}
+
+variable "local_targets" {
+  description = "Map of local services to expose via stunnel"
+  type = map(object({
+    listen_port = number
+    target_host = string
+    target_port = number
+    protocol    = string
+  }))
+  default = {}
+}
+
+variable "wireguard_config" {
+  description = "The Wireguard configuration file"
+  type = object({
+    private_key    = string
+    public_key     = string
+    pre_shared_key = string
+    endpoint       = string
+    endpoint_port  = number
+    address        = string
+    dns            = string
+    allowed_ips    = list(string)
+  })
+  default   = null
+  sensitive = true
+}
+
+variable "remote_targets" {
+  description = "Map of remote services to connect to via stunnel"
+  type = map(object({
+    listen_port = number
+    target_host = string
+    target_port = number
+    protocol    = string
+  }))
+  default = {}
+}