ci: auto-commit rustfmt fixes via dedicated workflow

Author: Cleboost

.github/workflows/ci.yml

@@ -10,16 +10,6 @@ env:
   RUSTFLAGS: -D warnings
 
 jobs:
-  fmt:
-    name: rustfmt
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v6
-      - uses: dtolnay/rust-toolchain@stable
-        with:
-          components: rustfmt
-      - run: cargo fmt --all -- --check
-
   clippy:
     name: clippy
     runs-on: ubuntu-latest

.github/workflows/rustfmt.yml

@@ -0,0 +1,23 @@
+name: rustfmt
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+permissions:
+  contents: write
+
+jobs:
+  rustfmt:
+    name: auto rustfmt
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt
+      - run: cargo fmt --all
+      - uses: stefanzweifel/git-auto-commit-action@v7
+        with:
+          commit_message: "style: apply rustfmt"