chore: freeze aws-cdk-lib floor at 2.190.0, add CDK compat CI matrix

Author: hrodmn

.github/dependabot.yml

@@ -6,6 +6,11 @@ updates:
       interval: "weekly"
     open-pull-requests-limit: 10
     versioning-strategy: "auto"
+    ignore:
+      # aws-cdk-lib and constructs are peer dependencies — their minimum floor
+      # is managed manually in package.json and should not be auto-bumped.
+      - dependency-name: "aws-cdk-lib"
+      - dependency-name: "constructs"
     groups:
       all-dependencies:
         patterns:

.github/workflows/cdk-compat.yaml

@@ -0,0 +1,27 @@
+name: CDK Compatibility
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+jobs:
+  check:
+    name: aws-cdk-lib@${{ matrix.aws-cdk-version }}
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        include:
+          - aws-cdk-version: "2.220.0"
+            constructs-version: "10.4.2"
+          - aws-cdk-version: "latest"
+            constructs-version: "latest"
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+      - run: npm run install:all
+      - run: npm install --no-save aws-cdk-lib@${{ matrix.aws-cdk-version }} constructs@${{ matrix.constructs-version }}
+      - run: npm run build