Reformat code and introduce rustfmt check in CI

Author: MarijnS95

.github/workflows/rust.yml

@@ -0,0 +1,12 @@
+name: Rust
+
+on: [push, pull_request]
+
+jobs:
+  formatting:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Format
+        run: cargo fmt --all -- --check