infra: introduce terraform/opentofu for proxmox management

- move ansible project within infra
- introduce terraform/opentofu for proxmox VM management

infra/terraform/proxmox/backend.tf

@@ -0,0 +1,14 @@
+terraform {
+  backend "s3" {
+    bucket                      = "terraform-state" # Name of the MinIO bucket
+    key                         = "proxmox/terraform.tfstate" # Path to the state file in the bucket
+    endpoint                    = var.minio_endpoint # MinIO API endpoint
+    access_key                  = var.minio_access_key # MinIO access key
+    secret_key                  = var.minio_secret_key # MinIO secret key
+    region                      = "us-east-1" # Arbitrary region (MinIO ignores this)
+    skip_credentials_validation = true # Skip AWS-specific credential checks
+    skip_metadata_api_check     = true # Skip AWS metadata API checks
+    skip_region_validation      = true # Skip AWS region validation
+    use_path_style              = true # Use path-style URLs[](http://<host>/<bucket>)
+  }
+}