ci: optimize workflow with caching, linting, and modern actions

- Replace deprecated actions-rs/toolchain with dtolnay/rust-toolchain
- Add Cargo registry and target directory caching
- Include rustfmt formatting checks and clippy linting
- Rename job from 'build' to 'test' with descriptive name

Author: eugener

.github/workflows/ci.yml

@@ -10,20 +10,38 @@ env:
   CARGO_TERM_COLOR: always
 
 jobs:
-  build:
-
+  test:
+    name: Test Suite
     runs-on: ubuntu-latest
 
     steps:
     - uses: actions/checkout@v4
+    
     - name: Install Rust Toolchain
-      uses: actions-rs/toolchain@v1 # Or actions-rust-lang/setup-rust-toolchain@v1
+      uses: dtolnay/rust-toolchain@stable
+      with:
+        toolchain: stable
+        components: rustfmt, clippy
+
+    - name: Cache Cargo registry
+      uses: actions/cache@v4
       with:
-        toolchain: stable # Use 'stable' to get the latest stable Rust
-        profile: minimal
-        override: true
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.os }}-cargo-
+
+    - name: Check formatting
+      run: cargo fmt -- --check
+
+    - name: Run Clippy
+      run: cargo clippy --all-targets --all-features -- -D warnings
 
     - name: Build
       run: cargo build --verbose
+
     - name: Run tests
       run: cargo test --verbose