chore(ci): remove mirror job (SSH key rotation pending)

Mirror to github.com was failing with 'unsupported in libcrypto' on every run
(OpenSSL 3.6 / OpenSSH 10 dropped support for the existing key format). Removed
rather than leave it polluting the CI signal. Re-add when the deploy key is
rotated to ed25519.

.gitea/workflows/ci.yml

@@ -90,24 +90,4 @@ jobs:
             && echo "Smoke test passed" \
             || echo "Smoke test inconclusive: $OUTPUT"
 
-  # ── 3. Mirror to GitHub (deploy intentionally omitted until manifests exist) ─
+  # ── 3. Mirror to GitHub — skipped for now (SSH key rotation pending) ─
-  mirror:
-    name: Mirror to GitHub
-    needs: build
-    runs-on: self-hosted
-    if: github.ref == 'refs/heads/main' && github.event_name == 'push'
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Push to GitHub
-        run: |
-          mkdir -p ~/.ssh
-          echo '${{ secrets.GH_DEPLOY_KEY }}' > ~/.ssh/id_rsa_gh_mirror
-          chmod 600 ~/.ssh/id_rsa_gh_mirror
-          ssh-keyscan github.com >> ~/.ssh/known_hosts 2>/dev/null
-          GIT_SSH_COMMAND="ssh -i ~/.ssh/id_rsa_gh_mirror -o IdentitiesOnly=yes" \
-            git push git@github.com:mathiasb/tapir.git HEAD:main
-          rm ~/.ssh/id_rsa_gh_mirror
-          echo "Mirrored to GitHub"