Add CI jobs for no_std checks

Author: engali94

.github/workflows/ci.yml

@@ -40,14 +40,21 @@ jobs:
       if: matrix.rust == 'stable'
       run: cargo clippy --all-targets -- -D warnings
 
+    - name: Run clippy (no_std)
+      if: matrix.rust == 'stable'
+      run: cargo clippy --all-targets --no-default-features -- -D warnings
+    
     - name: Build
       run: cargo build --verbose
 
     - name: Run tests
       run: cargo test --verbose
 
     - name: Run tests (no_std)
-      run: cargo test --no-default-features --features no_std --verbose
+      run: cargo test --no-default-features --verbose
+    
+    - name: Check no_std compilation
+      run: cargo check --no-default-features --verbose
 
     - name: Run tests (nightly features)
       if: matrix.rust == 'nightly'