chore(ci): install only Chromium for benchmark smoke

.changeset/famous-cameras-poke.md

@@ -0,0 +1,4 @@
+---
+---
+
+Install only Chromium for the benchmark smoke job; the full browser matrix remains in its dedicated portability job.

.github/workflows/ci.yml

@@ -113,8 +113,10 @@ jobs:
         run: bun install --frozen-lockfile
       - name: Install coverage toolchain
         run: cargo install cargo-llvm-cov --version "$CARGO_LLVM_COV_VERSION" --locked
-      - name: Install benchmark browser
-        run: bun run browser:install
+      # `bench:verify` launches Chromium only; Firefox and WebKit are exercised
+      # separately by `browser-smoke`.
+      - name: Install Chromium for the render smoke
+        run: bun run browser:install:chromium
       - name: Download canonical tarballs
         uses: actions/download-artifact@634f93cb2916e3fdff6788551b99b062d0335ce0 # v5
         with:

scripts/workflow-contract.test.ts

@@ -179,6 +179,10 @@ describe("CI and release workflow contracts", () => {
       expect(commands(workflows().ci.jobs[jobName]!)).toContain("bun run browser:install:chromium");
     }
 
+    const unitCoverageCommands = commands(workflows().ci.jobs["unit-coverage"]!).split("\n");
+    expect(unitCoverageCommands).toContain("bun run browser:install:chromium");
+    expect(unitCoverageCommands).not.toContain("bun run browser:install");
+
     const projectByName = Object.fromEntries(
       (playwrightConfig.projects ?? []).map((project) => [project.name, project]),
     );