ci/cd: add check for TODO comments

This commit introduces a new GitHub Actions job within the quality
checks workflow that scans the latest commit for TODO comments. The
intention is to prevent such comments from being merged into the main
branch, promoting cleaner and more maintainable code.

The script uses a specific pattern to avoid IDE detection and
misclassification of the script line as a TODO item itself. If any TODO
comments are found, the script exists with a non-zero status,
indicating an issue that must be addressed before proceeding.

.github/workflows/checks.quality.yaml

@@ -28,3 +28,22 @@ jobs:
       -
         name: Lint
         run: ${{ matrix.lint-command }}
+
+  todo-check:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Checkout
+        uses: actions/checkout@v4
+      -
+        name: Scan latest commit for TODO comments
+        shell: bash
+        run: |-
+          readonly todo_comment_search_pattern='TODO'':' # Define search pattern in parts to prevent IDE from flagging this script line as a TODO item
+          if git grep "$todo_comment_search_pattern" HEAD; then
+            echo 'TODO comments found in the latest commit.'
+            exit 1
+          else
+            echo 'No TODO comments found in the latest commit.'
+            exit 0
+          fi