fix: upgrade browse E2E runner to ubicloud-standard-8

Browse E2E tests launch concurrent Claude sessions + Playwright + browse
server. The standard-2 (2 vCPU / 8GB) container was getting OOM-killed
~30s in. Upgrade to standard-8 (8 vCPU / 32GB) for browse tests only —
all other suites stay on standard-2.

Uses matrix.suite.runner with a default fallback so only browse tests
get the bigger runner.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/actionlint.yaml

@@ -1,3 +1,4 @@
 self-hosted-runner:
   labels:
     - ubicloud-standard-2
+    - ubicloud-standard-8

.github/workflows/evals.yml

@@ -55,7 +55,7 @@ jobs:
             ${{ env.IMAGE }}:latest
 
   evals:
-    runs-on: ubicloud-standard-2
+    runs-on: ${{ matrix.suite.runner || 'ubicloud-standard-2' }}
     needs: build-image
     container:
       image: ${{ needs.build-image.outputs.image-tag }}
@@ -72,6 +72,7 @@ jobs:
             file: test/skill-llm-eval.test.ts
           - name: e2e-browse
             file: test/skill-e2e-browse.test.ts
+            runner: ubicloud-standard-8
           - name: e2e-plan
             file: test/skill-e2e-plan.test.ts
           - name: e2e-deploy