add dependabot, optimize CI

Author: cleot

.github/dependabot.yml

@@ -0,0 +1,19 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    groups:
+      all-github-actions:
+        patterns:
+          - "*"
+    schedule:
+      interval: "monthly"
+      day: "monday"
+      time: "08:30"
+      timezone: "Europe/Vienna"
+    open-pull-requests-limit: 5
+    labels:
+      - "dependencies"
+      - "github-actions"
+    assignees:
+      - "cleot" # devops

.github/workflows/build.yml

@@ -0,0 +1,40 @@
+name: CI
+
+on:
+  push:
+    branches: ["*"]
+  pull_request:
+    branches: ["*"]
+
+jobs:
+  validate:
+    name: Validate (lint, test, build)
+    runs-on: ubuntu-latest
+    env:
+      NODE_VERSION: 22
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
+
+      - name: Set up Node.js (${{ env.NODE_VERSION }})
+        uses: actions/setup-node@2028fbc5c25fe9cf00d9f06a71cc4710d4507903 # v6.0.0
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Lint
+        run: npm run lint
+
+      - name: Run tests and generate coverage
+        run: npm run test -- --coverage
+
+      - name: Build
+        run: npm run build
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@5a1091511ad55cbe89839c7260b706298ca349f7 # v5.5.1
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}