ci: add GitHub Actions CI and release workflows

- CI runs build, lint, and unit tests on Node 18/20 for develop/master PRs
- Release workflow triggers on v* tags: builds, tests, publishes to npm, creates GitHub Release

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Ziut3k-dev

.github/workflows/ci.yml

@@ -0,0 +1,41 @@
+name: CI
+
+on:
+  push:
+    branches: [develop, master]
+  pull_request:
+    branches: [develop, master]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [18.x, 20.x]
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+          cache: npm
+
+      - run: npm ci
+
+      - name: Build
+        run: npm run build
+
+      - name: Lint
+        run: npm run lint
+
+      - name: Unit tests
+        run: jest --testPathPatterns=spec
+
+      - name: Upload coverage
+        uses: actions/upload-artifact@v4
+        if: matrix.node-version == '20.x'
+        with:
+          name: coverage
+          path: coverage/

.github/workflows/release.yml

@@ -0,0 +1,41 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*.*.*'
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Use Node.js 20
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20.x'
+          registry-url: 'https://registry.npmjs.org'
+          cache: npm
+
+      - run: npm ci
+
+      - name: Build
+        run: npm run build
+
+      - name: Unit tests
+        run: jest --testPathPatterns=spec
+
+      - name: Publish to npm
+        run: npm publish --access public
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          generate_release_notes: true
+          body_path: CHANGELOG.md