ci(workflow): add auto-sync dev after main release

Automatically merges main into dev after Release workflow completes.
Keeps dev ahead with next version number after stable releases.

.github/workflows/sync-dev-after-release.yml

@@ -0,0 +1,35 @@
+name: Sync Dev After Main Release
+
+on:
+  workflow_run:
+    workflows: ["Release"]
+    types: [completed]
+    branches: [main]
+
+jobs:
+  sync-dev:
+    # Only run if Release workflow succeeded on main branch
+    if: ${{ github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.head_branch == 'main' }}
+    runs-on: ubuntu-latest
+
+    permissions:
+      contents: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          token: ${{ secrets.PAT_TOKEN }}
+
+      - name: Configure Git
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+
+      - name: Sync dev with main
+        run: |
+          git fetch origin main dev
+          git checkout dev
+          git merge origin/main --no-edit -m "chore(sync): merge main into dev after release [skip ci]"
+          git push origin dev