Fix AUR publish SSH handling in release workflow

[Copilot]

The Release artifacts and AUR GitHub Actions job was failing during AUR publish because SSH host/key handling was not consistently applied to git operations in the push step. This change makes AUR git clone/push use explicit SSH settings in that step.

• Workflow fix: enforce SSH config for AUR git operations

  • Updated .github/workflows/release.yml in Push AUR packages to export GIT_SSH_COMMAND before any git remote operation.
  • This ensures git uses the injected AUR key, enforces identity selection, and uses the expected known-hosts file.

• Why this addresses the failure

  • Prevents Host key verification failed during git clone/git push to aur.archlinux.org.
  • Aligns SSH behavior across all git invocations in the step instead of relying on ambient ssh config resolution.

- name: Push AUR packages
  if: env.AUR_SSH_PRIVATE_KEY != ''
  run: |
    export GIT_SSH_COMMAND="ssh -i $HOME/.ssh/aur -o IdentitiesOnly=yes -o StrictHostKeyChecking=accept-new -o UserKnownHostsFile=$HOME/.ssh/known_hosts"
    mkdir -p "$RUNNER_TEMP/aur"
    # clone/commit/push loop...