ci: sync upstream

.github/workflows/sync.yaml

@@ -0,0 +1,45 @@
+name: 'Upstream Sync'
+
+on:
+  schedule:
+    - cron:  '0 0 * * 4'
+
+  workflow_dispatch:
+    inputs:
+      sync_test_mode:
+        description: 'Fork Sync Test Mode'
+        type: boolean
+        default: false
+
+jobs:
+  sync_latest_from_upstream:
+    runs-on: ubuntu-latest
+    name: Sync latest commits from upstream repo
+
+    steps:
+    - name: Checkout target repo
+      uses: actions/checkout@v4
+      with:
+        ref: perf
+
+    - name: Sync upstream changes
+      id: sync
+      uses: aormsby/Fork-Sync-With-Upstream-action@v3.4
+      with:
+        target_sync_branch: perf
+        upstream_sync_branch: main
+        upstream_sync_repo: hrsh7th/nvim-cmp
+        test_mode: ${{ inputs.sync_test_mode }}
+        git_config_pull_rebase: true
+        target_branch_push_args: '--force'
+
+    - name: New commits found
+      if: steps.sync.outputs.has_new_commits == 'true'
+      run: echo "New commits were found to sync."
+
+    - name: No new commits
+      if: steps.sync.outputs.has_new_commits == 'false'
+      run: echo "There were no new commits."
+
+    - name: Show value of 'has_new_commits'
+      run: echo ${{ steps.sync.outputs.has_new_commits }}