Add Github workspace mirror.yml so we can pull to github daily

This operates only on github, where it will result in a daily mirror operation.

.github/workflows/mirror.yml

+name: Mirror from Upstream
+
+on:
+  schedule:
+    - cron: '0 0 * * *'  # Runs daily at midnight UTC
+  workflow_dispatch:     # Allows manual triggering of the workflow
+
+jobs:
+  mirror:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Set up Git environment
+        run: |
+          git config --global user.name "GitHub Action"
+          git config --global user.email "action@github.com"
+
+      - name: Clone upstream repository
+        run: |
+          git clone --mirror ${UPSTREAM_REPO} tempdir
+
+      - name: Push to GitHub
+        env:
+          UPSTREAM_REPO: ${{ vars.UPSTREAM_REPO }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          REPO: ${{ github.repository }}
+
+        run: |
+          cd tempdir
+
+          git remote set-url --push origin "https://x-access-token:${GITHUB_TOKEN}@github.com/${REPO}.git"
+          git push --mirror