feat: add Slack notification on release and CODEOWNERS

.github/CODEOWNERS

@@ -0,0 +1 @@
+*  @kosli-dev/customer-success

.github/workflows/publish.yml

@@ -5,6 +5,15 @@ on:
     types: [published, edited]
 
 jobs:
+  notify-start:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: kosli-dev/reusable-actions/slack-release-notify@main
+        with:
+          slack-bot-token: ${{ secrets.SLACK_BOT_TOKEN }}
+          slack-channel-id: ${{ vars.SLACK_CHANNEL_ID }}
+          stage: start
+
   build:
     name: Build
     runs-on: ubuntu-latest
@@ -18,3 +27,27 @@ jobs:
       - uses: JasonEtco/build-and-tag-action@v2
         env:
           GITHUB_TOKEN: ${{ github.token }}
+
+  notify-finish:
+    needs: [notify-start, build]
+    if: always() && needs.notify-start.result == 'success'
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read     # ← needed to fetch run_started_at for duration
+      contents: read    # ← needed to read release notes via `gh release view`
+    steps:
+      - name: Determine status
+        id: status
+        run: |
+          if [[ "${{ needs.build.result }}" == "success" ]]; then
+            echo "value=success" >> "$GITHUB_OUTPUT"
+          else
+            echo "value=failure" >> "$GITHUB_OUTPUT"
+          fi
+
+      - uses: kosli-dev/reusable-actions/slack-release-notify@main
+        with:
+          slack-bot-token: ${{ secrets.SLACK_BOT_TOKEN }}
+          slack-channel-id: ${{ vars.SLACK_CHANNEL_ID }}
+          stage: finish
+          status: ${{ steps.status.outputs.value }}