Add a GHA that create a git tag weekly

.github/workflows/publish.yaml

@@ -2,8 +2,9 @@ name: "Publish a flake to flakestry"
 on:
     push:
         tags:
-        - "v?[0-9]+.[0-9]+.[0-9]+"
-        - "v?[0-9]+.[0-9]+"
+          # This pattern matches tags in the format YYYY.MM.DD
+          # It expects a four-digit year, followed by a two-digit month and day
+          - "[0-9]{4}.[0-9]{2}.[0-9]{2}"
     workflow_dispatch:
         inputs:
             tag:

.github/workflows/tag.yml

@@ -0,0 +1,25 @@
+name: "Weekly Date Tag"
+
+on:
+  schedule:
+    - cron: '0 0 * * 0'
+
+jobs:
+  tag-repo:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Create and push tag using current date
+        run: |
+          TAG_DATE=$(date -u "+%Y.%m.%d")
+          if git rev-parse "$TAG_DATE" >/dev/null 2>&1; then
+              echo "Tag $TAG_DATE already exists. Skipping tag creation."
+          else
+              git config user.name "github-actions"
+              git config user.email "[email protected]"
+              git tag $TAG_DATE
+              git push origin $TAG_DATE
+          fi