Version bump, Style guide, dns records updates optional, and input validation

variable.image.tf

@@ -1,4 +1,10 @@
 variable "image" {
-  default = "linode/fedora38"
-  type    = string
+  default     = "linode/fedora44"
+  description = "An Image ID to deploy the Disk from."
+  type        = string
+
+  validation {
+    condition     = can(regex("^[a-zA-Z0-9-]+/[a-zA-Z0-9.-]+$", var.image))
+    error_message = "The image must be a valid Linode image ID (e.g., linode/fedora44)."
+  }
 }