Replace force-push sync with PR-based auto-merge workflow

.github/workflows/auto-merge.yml

@@ -0,0 +1,47 @@
+name: Auto Merge
+
+on:
+  workflow_run:
+    workflows: ["CI"]
+    types: [completed]
+
+jobs:
+  auto-merge:
+    runs-on: ubuntu-latest
+    if: >
+      github.event.workflow_run.conclusion == 'success' &&
+      github.event.workflow_run.event == 'pull_request'
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Find and merge master → main PR
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          HEAD_BRANCH="${{ github.event.workflow_run.head_branch }}"
+          echo "Workflow ran on branch: $HEAD_BRANCH"
+
+          if [ "$HEAD_BRANCH" != "master" ]; then
+            echo "Not a master branch PR, skipping"
+            exit 0
+          fi
+
+          PR_NUMBER=$(gh pr list \
+            --repo "$GITHUB_REPOSITORY" \
+            --base main \
+            --head master \
+            --state open \
+            --json number \
+            --jq '.[0].number')
+
+          if [ -z "$PR_NUMBER" ]; then
+            echo "No open PR from master to main found, skipping"
+            exit 0
+          fi
+
+          echo "Merging PR #$PR_NUMBER"
+          gh pr merge "$PR_NUMBER" \
+            --repo "$GITHUB_REPOSITORY" \
+            --merge \
+            --delete-branch=false

.github/workflows/auto-pr.yml

@@ -0,0 +1,34 @@
+name: Auto PR (master → main)
+
+on:
+  push:
+    branches: [master]
+
+jobs:
+  create-pr:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Create or update PR
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          EXISTING_PR=$(gh pr list --base main --head master --state open --json number --jq '.[0].number')
+
+          if [ -n "$EXISTING_PR" ]; then
+            echo "PR #$EXISTING_PR already exists — new commits will appear automatically"
+          else
+            echo "Creating new PR: master → main"
+            gh pr create \
+              --base main \
+              --head master \
+              --title "Sync: master → main" \
+              --body "Automated PR to sync master branch changes to main.
+
+          This PR was created automatically and will be merged once CI checks pass."
+          fi

.github/workflows/sync-branches.yml

@@ -1,36 +0,0 @@
-name: Sync main and master branches
-
-on:
-  push:
-    branches:
-      - main
-      - master
-
-jobs:
-  sync:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: write
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-          token: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Sync branches
-        run: |
-          git config user.name "github-actions[bot]"
-          git config user.email "github-actions[bot]@users.noreply.github.com"
-
-          if [ "${{ github.ref }}" = "refs/heads/main" ]; then
-            echo "main was updated, syncing master..."
-            git checkout master
-            git reset --hard origin/main
-            git push origin master --force
-          elif [ "${{ github.ref }}" = "refs/heads/master" ]; then
-            echo "master was updated, syncing main..."
-            git checkout main
-            git reset --hard origin/master
-            git push origin main --force
-          fi