add benchmarks and run in codspeed

.github/workflows/bench.yml

@@ -0,0 +1,30 @@
+name: bench
+
+on:
+  pull_request:
+  push:
+    branches: [main]
+  workflow_dispatch:
+
+jobs:
+  benchmarks:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          persist-credentials: false
+
+      - uses: moonrepo/setup-rust@v1
+        with:
+          channel: stable
+          cache-target: release
+          bins: cargo-codspeed
+
+      - name: Build the benchmark target(s)
+        run: cargo codspeed build
+
+      - name: Run the benchmarks
+        uses: CodSpeedHQ/action@v4
+        with:
+          mode: instrumentation
+          run: cargo codspeed run