Remove temporary debug workflow

.gitea/workflows/debug-key.yaml

@@ -1,18 +0,0 @@
-name: debug-key
-
-on:
-  workflow_dispatch:
-
-jobs:
-  debug:
-    runs-on: deploy
-    steps:
-      - name: Inspect CI_SSH_KEY shape (no secret content exposed)
-        env:
-          CI_SSH_KEY: ${{ secrets.CI_SSH_KEY }}
-        run: |
-          echo "line count: $(printf '%s' "$CI_SSH_KEY" | wc -l)"
-          echo "char count: $(printf '%s' "$CI_SSH_KEY" | wc -c)"
-          printf '%s' "$CI_SSH_KEY" | head -c 30
-          echo
-          printf '%s' "$CI_SSH_KEY" | tail -c 30