Add smoke test workflow

.github/workflows/main.yml

@@ -0,0 +1,20 @@
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+jobs:
+  smoke-test:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install Swift toolchain
+        run:
+          toolchain_path="/opt/swift"
+          curl -L https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT-SNAPSHOT-2024-09-25-a/swift-DEVELOPMENT-SNAPSHOT-2024-09-25-a-ubuntu22.04.tar.gz | tar xz --strip-component 1 -C "$toolchain_path"
+          echo "export PATH=$toolchain_path/usr/bin:$PATH" >> $GITHUB_ENV
+      - uses: bytecodealliance/actions/wasmtime/setup@v1
+      - name: Build
+        run: swift build -c release --triple wasm32-unknown-none-wasm -debug-info-format=none
+      - name: Test
+        run: wasmtime run .build/release/Examples.wasm