fix: remove versions.tf and exclude modules from validate/tflint

The versions.tf conflicts with terragrunt's generated backend.tf which
already has required_providers. Exclude modules/ from tofu-validate and
tflint pre-commit hooks since they can't init without the full terragrunt
context.

modules/prowlarr/versions.tf

@@ -1,9 +0,0 @@
-terraform {
-  required_version = ">= 1.10"
-  required_providers {
-    prowlarr = {
-      source  = "devopsarr/prowlarr"
-      version = ">= 3.2.1"
-    }
-  }
-}