Add harness infrastructure for web-shell package (#6517)

* test(web-shell): add browser and lint harness

* test(web-shell): harden browser smoke harness

* fix(web-shell): guard mock daemon model state

* test(web-shell): remove unused scenario harness

* fix(web-shell): remove stale lint disables

* test(web-shell): make matchMedia stub writable

* fix(web-shell): exclude tests from package typecheck

* test(web-shell): tighten mock daemon route contract

* Update packages/web-shell/client/e2e/utils/mockDaemon.ts

Co-authored-by: qwen-code-ci-bot <qwen-code-ci@service.alibaba.com>

* test(web-shell): clear stale SSE connections

* ci(web-shell): gate smoke on full CI profile

---------

Co-authored-by: ermin.zem <ermin.zem@alibaba-inc.com>
Co-authored-by: qwen-code-ci-bot <qwen-code-ci@service.alibaba.com>
Co-authored-by: Shaojin Wen <shaojin.wensj@alibaba-inc.com>
Co-authored-by: 易良 <1204183885@qq.com>

.github/workflows/e2e.yml

@@ -144,3 +144,47 @@ jobs:
           OPENAI_BASE_URL: '${{ secrets.OPENAI_BASE_URL }}'
           OPENAI_MODEL: '${{ secrets.OPENAI_MODEL }}'
         run: 'npm run test:e2e'
+
+  web-shell-browser-regression:
+    name: 'web-shell Browser Regression'
+    runs-on: 'ubuntu-latest'
+    if: |-
+      ${{ github.event_name == 'schedule' || github.event_name == 'workflow_dispatch' }}
+    steps:
+      - name: 'Checkout'
+        uses: 'actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd' # v6.0.2
+
+      - name: 'Set up Node.js'
+        uses: 'actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e' # v6.4.0
+        with:
+          node-version-file: '.nvmrc'
+          cache: 'npm'
+          cache-dependency-path: 'package-lock.json'
+          registry-url: 'https://registry.npmjs.org/'
+
+      - name: 'Configure npm for rate limiting'
+        run: |-
+          npm config set fetch-retry-mintimeout 20000
+          npm config set fetch-retry-maxtimeout 120000
+          npm config set fetch-retries 5
+          npm config set fetch-timeout 300000
+
+      - name: 'Install dependencies'
+        run: |-
+          npm ci --prefer-offline --no-audit --progress=false
+
+      - name: 'Install Playwright Chromium'
+        run: 'npx playwright install --with-deps chromium'
+
+      - name: 'Run web-shell browser regression'
+        run: 'npm run test:e2e --workspace=packages/web-shell'
+
+      - name: 'Upload web-shell Playwright artifacts'
+        if: '${{ always() }}'
+        uses: 'actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a' # v7.0.1
+        with:
+          name: 'web-shell-browser-regression'
+          path: |-
+            packages/web-shell/client/e2e/test-results
+            packages/web-shell/client/e2e/playwright-report
+          if-no-files-found: 'ignore'