ci: speed up Terraform plan by skipping refresh in pipelines

Use terraform plan -refresh=false in plan/apply workflows to avoid slow Proxmox state refresh on every push. This keeps CI fast while preserving apply behavior from the generated plan.

.gitea/workflows/terraform-apply.yml

@@ -57,7 +57,7 @@ jobs:
           set -euo pipefail
           for attempt in 1 2; do
             echo "Terraform plan attempt $attempt/2"
-            if timeout 20m terraform plan -parallelism=1 -out=tfplan; then
+            if timeout 20m terraform plan -refresh=false -parallelism=1 -out=tfplan; then
               exit 0
             fi
             if [ "$attempt" -eq 1 ]; then