name: CI Cross-Version Upgrade

permissions:
  contents: read

on:
  push:
    tags:
      - 'v[0-9]+.[0-9]+.[0-9]+'
  workflow_dispatch:

jobs:
  cross-version-upgrade:
    timeout-minutes: 45
    runs-on: ubuntu-latest
    steps:
      - name: Placeholder
        run: echo "Cross-version upgrade CI — not yet implemented"