init: Add rust workspace with toolchain version fixed on current latest stable.

script: Add github action for linting and compile checking.

.github/workflows/ci.yml

@@ -0,0 +1,72 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  check:
+    name: Check
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy, rustfmt
+      - uses: Swatinem/rust-cache@v2
+      - name: Check
+        run: cargo check --workspace --all-targets
+
+  clippy:
+    name: Clippy (strict)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy
+      - uses: Swatinem/rust-cache@v2
+      - name: Clippy
+        run: |
+          cargo clippy --workspace --all-targets -- \
+            -D warnings \
+            -D clippy::unwrap_used \
+            -D clippy::expect_used \
+            -D clippy::panic \
+            -D clippy::unimplemented \
+            -D clippy::todo \
+            -D clippy::dbg_macro \
+            -D clippy::print_stdout \
+            -D clippy::print_stderr
+
+  fmt:
+    name: Format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt
+      - name: Rustfmt
+        run: cargo fmt --all -- --check
+
+  test:
+    name: Test
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
+      - name: Run tests
+        run: cargo test --workspace