chore: disable VM tailscale bootstrap for now

Remove tailscale auth/bootstrap from cloud-init and workflows, keeping VM provisioning focused on core network behind pfSense while preserving SSH key cloud-init setup.

.gitea/workflows/terraform-destroy.yml

@@ -44,7 +44,6 @@ jobs:
           cat > secrets.auto.tfvars << EOF
           pm_api_token_secret = "${{ secrets.PM_API_TOKEN_SECRET }}"
           SSH_KEY_PUBLIC      = "$(printf '%s' "${{ secrets.SSH_KEY_PUBLIC }}" | tr -d '\r\n')"
-          TS_AUTHKEY          = "$(printf '%s' "${{ secrets.TS_AUTHKEY }}" | tr -d '\r\n')"
           EOF
           cat > backend.hcl << EOF
           bucket                      = "${{ secrets.B2_TF_BUCKET }}"