CI: added some "basic" GitHub Actions.

.github/workflows/ci.yml

@@ -0,0 +1,71 @@
+name: CI
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+  workflow_dispatch:
+
+jobs:
+  cpp:
+    name: ${{ matrix.name }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: 'Windows static library'
+            os: windows-latest
+            build_shared: OFF
+          - name: 'Windows shared library'
+            os: windows-latest
+            build_shared: ON
+          - name: 'Linux static library'
+            os: ubuntu-latest
+            build_shared: OFF
+          - name: 'Linux shared library'
+            os: ubuntu-latest
+            build_shared: ON
+          - name: 'macOS static library (Intel)'
+            os: macos-13
+            build_shared: OFF
+          - name: 'macOS shared library (Intel)'
+            os: macos-13
+            build_shared: ON
+          - name: 'macOS static library (ARM)'
+            os: macos-latest
+            build_shared: OFF
+          - name: 'macOS shared library (ARM)'
+            os: macos-latest
+            build_shared: ON
+    env:
+      BUILDCACHE_ACCURACY: STRICT
+      BUILDCACHE_COMPRESS_FORMAT: ZSTD
+      BUILDCACHE_DEBUG: -1
+      BUILDCACHE_LOG_FILE: ""
+    steps:
+      - name: Check out libCellML
+        uses: actions/checkout@v4
+      - name: Install CMake and Ninja
+        uses: lukka/get-cmake@latest
+      - name: Install buildcache
+        uses: mikehardy/buildcache-action@v2
+        with:
+          cache_key: ${{ matrix.os }}-${{ matrix.build_shared }}
+      - name: Configure MSVC
+        if: ${{ runner.os == 'Windows' }}
+        uses: ilammy/msvc-dev-cmd@v1
+      - name: Configure libCellML
+        run: |
+          mkdir build
+          cd build
+          cmake -G Ninja -DBUILD_SHARED=${{ matrix.build_shared }} -DBINDINGS_PYTHON=OFF -DCOVERAGE=OFF -DLLVM_COVERAGE=OFF ..
+      - name: Build libCellML
+        run: |
+          cd build
+          ninja
+      - name: Unit testing
+        run: |
+          cd build
+          ninja test