feat: Add Playwright browser caching to CI workflows (#5272)

Improves CI performance by caching Playwright browsers between runs.
This reduces the time spent downloading browsers on each workflow execution.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-authored-by: Claude <noreply@anthropic.com>

.github/workflows/i18n.yaml

@@ -25,6 +25,13 @@ jobs:
         key: i18n-tools-cache-${{ runner.os }}-${{ hashFiles('ComfyUI_frontend/pnpm-lock.yaml') }}
         restore-keys: |
           i18n-tools-cache-${{ runner.os }}-
+    - name: Cache Playwright browsers
+      uses: actions/cache@v4
+      with:
+        path: ~/.cache/ms-playwright
+        key: playwright-browsers-${{ runner.os }}-${{ hashFiles('ComfyUI_frontend/pnpm-lock.yaml') }}
+        restore-keys: |
+          playwright-browsers-${{ runner.os }}-
     - name: Install Playwright Browsers
       run: npx playwright install chromium --with-deps
       working-directory: ComfyUI_frontend

.github/workflows/test-browser-exp.yaml

@@ -11,6 +11,13 @@ jobs:
     if: github.event.label.name == 'New Browser Test Expectations'
     steps:
     - uses: Comfy-Org/ComfyUI_frontend_setup_action@v3
+    - name: Cache Playwright browsers
+      uses: actions/cache@v4
+      with:
+        path: ~/.cache/ms-playwright
+        key: playwright-browsers-${{ runner.os }}-${{ hashFiles('ComfyUI_frontend/pnpm-lock.yaml') }}
+        restore-keys: |
+          playwright-browsers-${{ runner.os }}-
     - name: Install Playwright Browsers
       run: npx playwright install chromium --with-deps
       working-directory: ComfyUI_frontend