ci: build the benchmark environment outside the CodSpeed runner (#38426)

Co-authored-by: yassin <yassin@berri.ai>
Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.github/workflows/codspeed.yml

@@ -12,6 +12,7 @@ on:
       - "uv.lock"
       - ".github/workflows/codspeed.yml"
       - ".github/actions/setup-uv-with-retries/**"
+      - ".github/actions/cache-cargo-build/**"
   pull_request:
     branches:
       - main
@@ -23,6 +24,7 @@ on:
       - "uv.lock"
       - ".github/workflows/codspeed.yml"
       - ".github/actions/setup-uv-with-retries/**"
+      - ".github/actions/cache-cargo-build/**"
   # Allow CodSpeed to trigger backtest performance analysis
   # in order to generate initial data
   workflow_dispatch:
@@ -55,6 +57,26 @@ jobs:
         with:
           version: "0.10.9"
 
+      - name: Cache the Rust build
+        uses: ./.github/actions/cache-cargo-build
+
+      # Build the wheel and resolve every dependency outside the CodSpeed
+      # runner: the same maturin build took 42 minutes inside `codspeed run`
+      # versus under 3 minutes as a plain step (LIT-6183)
+      - name: Build environment
+        run: >
+          env PYTEST_DISABLE_PLUGIN_AUTOLOAD=1
+          uv run --frozen --no-default-groups
+          --with pytest==8.3.5
+          --with pytest-codspeed==4.3.0
+          --with "mcp>=1.26.0,<2.0"
+          --with "a2a-sdk>=1.1.0,<2.0"
+          pytest
+          -p pytest_codspeed.plugin
+          tests/benchmarks/
+          --codspeed
+          --collect-only -q
+
       - name: Run benchmarks
         uses: CodSpeedHQ/action@1c8ae4843586d3ba879736b7f6b7b0c990757fab # v4.12.1
         with: