ci: validate hardcoded fallback IP pin behavior

Author: nichu42

.github/workflows/diag-fallback.yml

@@ -0,0 +1,38 @@
+name: Validate fallback IP pin behavior
+
+on:
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install rclone
+        run: curl -fsSL https://rclone.org/install.sh | sudo bash
+
+      - name: "Replicate failing scenario: pin hardcoded IP + raw endpoint"
+        env:
+          ENDPOINT: ${{ secrets.HOMEPAGE_BUNNY_S3_ENDPOINT }}
+          ACCESS: ${{ secrets.HOMEPAGE_BUNNY_S3_ACCESS_KEY }}
+          SECRET: ${{ secrets.HOMEPAGE_BUNNY_S3_SECRET_KEY }}
+          BUCKET: ${{ secrets.HOMEPAGE_BUNNY_S3_BUCKET }}
+        run: |
+          HOST=$(echo "$ENDPOINT" | sed -E 's#^https?://##; s#[/:].*##')
+          echo "$HOST" | sed 's/^/host: /'
+          echo "109.61.89.53 $HOST" | sudo tee -a /etc/hosts >/dev/null
+          cat /etc/hosts | tail -3
+          mkdir -p ~/.config/rclone
+          cat > ~/.config/rclone/rclone.conf <<EOF
+          [bunny]
+          type = s3
+          provider = Other
+          env_auth = false
+          access_key_id = ${ACCESS}
+          secret_access_key = ${SECRET}
+          endpoint = ${ENDPOINT}
+          force_path_style = true
+          acl = private
+          EOF
+          echo "=== lsd with pinned 109.61.89.53 ==="
+          timeout 60 rclone lsd "bunny:${BUCKET}" --fast-list --verbose 2>&1 | tail -20
+          echo "EXIT: $?"