Feat: init github workflows

.github/workflows/greetings.yml

@@ -0,0 +1,16 @@
+name: Greetings
+
+on: [pull_request, issues]
+
+jobs:
+  greeting:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+    - uses: actions/first-interaction@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        issue-message: 'Hi @${{ github.actor }}, thanks for opening this issue.'
+        pr-message: 'Hi @${{ github.event.pull_request.user.login }}, Thank you for taking your time and effort for your contribution, we truly value it. :tada:'