CI: add build + lint + test job

.github/workflows/code.yml

@@ -0,0 +1,37 @@
+name: CI
+
+on:
+  pull_request:
+    branches: [master]
+
+jobs:
+  build-lint-test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt, clippy
+
+      - name: Install protoc
+        uses: arduino/setup-protoc@v3
+
+      - name: Cache cargo
+        uses: Swatinem/rust-cache@v2
+
+      - name: Install Task
+        uses: arduino/setup-task@v2
+        with:
+          version: 3.x
+
+      - name: Check formatting
+        run: task fmt:check
+
+      - name: Run clippy
+        run: task lint
+
+      - name: Run tests
+        run: task test

Taskfile.yml

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+version: "3"
+
+tasks:
+  fmt:
+    desc: "Format Rust code"
+    cmds: [cargo fmt]
+
+  fmt:check:
+    desc: "Check Rust code formatting"
+    cmds: [ cargo fmt --check]
+
+  lint:
+    desc: "Lint Rust code"
+    cmds: [cargo clippy --all-targets --all-features -- -D warnings]
+
+  test:
+    desc: "Test Rust code"
+    cmds:
+      # We want to be sure every workspace member is always tested.
+      # However, some members need special parameters
+      # (e.g. event-plugin tests must run in a single thread),
+      # so a single 'cargo test' can't cover everything correctly.
+      # Therefore, task:test runs every workspace member EXCEPT the
+      # excluded ones (e.g. event-plugin), and the excluded members
+      # are run separately with their own command.
+      - cargo test --workspace --exclude event-plugin
+      - cargo test -p event-plugin -- --test-threads=1