feat(setup): add 'clean' subcommand to remove generated files

Add ./setup clean to remove:
- inventory/hosts.yml and host_vars/web.yml
- terraform/tfplan
- scripts/__pycache__
- .DS_Store files

setup

@@ -7,7 +7,7 @@ temp_vault_pass_file=""
 
 usage() {
   cat <<'EOF'
-Usage: ./setup [--no-ansible] [--no-terraform|--ansible-only] [--] [terraform <args>]
+Usage: ./setup [--no-ansible] [--no-terraform|--ansible-only] [clean] [--] [terraform <args>]
 
 Defaults:
   - Runs Terraform (plan/apply) in terraform/
@@ -18,6 +18,7 @@ Options:
   --no-ansible        Run Terraform only (no Ansible).
   --no-terraform      Skip Terraform; requires existing inventory/hosts.yml.
   --ansible-only      Alias for --no-terraform.
+  clean               Remove generated files (inventory, tfplan, cache).
   --help              Show this help.
 
 Terraform passthrough:
@@ -44,6 +45,16 @@ if [[ "${1:-}" == "--help" ]] || [[ "${1:-}" == "-h" ]]; then
   exit 0
 fi
 
+if [[ "${1:-}" == "clean" ]]; then
+  echo "Cleaning up generated files..."
+  rm -f inventory/hosts.yml inventory/host_vars/web.yml
+  rm -f terraform/tfplan
+  rm -rf scripts/__pycache__
+  find . -name ".DS_Store" -delete 2>/dev/null || true
+  echo "Cleanup complete."
+  exit 0
+fi
+
 if [[ "${1:-}" == "--no-ansible" ]]; then
   run_ansible=false
   shift