ci: add Codecov PR comments and conventional commit PR title check (#19)

- Add codecov.yml with project coverage display in PR comments
- Add pr-title.yaml workflow to enforce conventional commit format on PR titles

Author: marcinpsk

.github/workflows/pr-title.yaml

@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (C) 2025 Marcin Zieba <marcinpsk@gmail.com>
+name: Validate PR title
+
+on:
+  pull_request_target:
+    types: [opened, edited, synchronize]
+
+permissions:
+  pull-requests: read
+
+jobs:
+  lint-pr-title:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Enforce conventional commit PR title
+        uses: amannn/action-semantic-pull-request@0723387faaf9b38adef4775cd42cfd5155ed6017  # v5.5.3
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          types: |
+            feat
+            fix
+            docs
+            style
+            refactor
+            perf
+            test
+            build
+            ci
+            chore
+            revert
+          requireScope: false
+          subjectPattern: ^.+$
+          subjectPatternError: "PR title must not be empty after the type/scope prefix."

codecov.yml

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (C) 2025 Marcin Zieba <marcinpsk@gmail.com>
+comment:
+  layout: "diff, flags, files"
+  behavior: default
+  require_changes: false
+  require_base: false
+  require_head: true
+  hide_project_coverage: false