ci: add Emscripten WASM build job

Add emscripten-wasm job to CI workflow:
- Uses mymindstorm/setup-emsdk with Emscripten 3.1.61
- Configures with -DOPENDRIVE_BUILD_WASM=ON and Ninja generator
- Builds WASM artifacts (libOpenDRIVE.js + .wasm)
- Verifies artifact presence after build

Signed-off-by: Carlo van Driesten <carlo.van-driesten@bmw.de>

Author: jdsika

.github/workflows/ci.yaml

@@ -44,4 +44,25 @@ jobs:
       - name: test
         run: ctest --test-dir build --output-on-failure
       - name: install
-        run: cmake --install build --config Release
+        run: cmake --install build --config Release
+  build-wasm:
+    name: emscripten-wasm
+    runs-on: ubuntu-22.04
+    defaults:
+      run:
+        shell: bash -e -o pipefail {0}
+    steps:
+      - name: checkout repository
+        uses: actions/checkout@v4
+      - name: setup emsdk
+        uses: mymindstorm/setup-emsdk@v14
+        with:
+          version: 3.1.61
+      - name: configure
+        run: emcmake cmake -S . -B build-wasm -DOPENDRIVE_BUILD_WASM=ON -G Ninja
+      - name: build
+        run: cmake --build build-wasm
+      - name: verify artifacts
+        run: |
+          test -f build-wasm/libOpenDRIVE.js
+          test -f build-wasm/libOpenDRIVE.wasm