[feat] Re-add ComfyUI loading GIF to workflow status comments (#5277)

Restore the ComfyUI animated favicon loading indicator to PR status
comments that was removed in PR #5209 when workflow architecture was
restructured. The loading GIF now appears in:

- Playwright test status comments (pr-playwright-comment.yaml)
- Storybook build status comments (pr-storybook-comment.yaml)

This provides visual continuity and branding consistency during
CI operations, replacing generic hourglass emoji with ComfyUI's
animated logo.

.github/workflows/pr-playwright-comment.yaml

@@ -50,7 +50,7 @@ jobs:
           echo "<!-- PLAYWRIGHT_TEST_STATUS -->" > comment.md
           echo "## 🎭 Playwright Test Results" >> comment.md
           echo "" >> comment.md
-          echo "⏳ **Tests are starting...** " >> comment.md
+          echo "<img alt='comfy-loading-gif' src='https://github.com/user-attachments/assets/755c86ee-e445-4ea8-bc2c-cca85df48686' width='14px' height='14px' style='vertical-align: middle; margin-right: 4px;' /> **Tests are starting...** " >> comment.md
           echo "" >> comment.md
           echo "⏰ Started at: ${{ steps.completion-time.outputs.time }} UTC" >> comment.md
           echo "" >> comment.md

.github/workflows/pr-storybook-comment.yaml

@@ -73,7 +73,7 @@ jobs:
             <!-- STORYBOOK_BUILD_STATUS -->
             ## 🎨 Storybook Build Status
 
-            ⏳ **Build is starting...** 
+            <img alt='comfy-loading-gif' src='https://github.com/user-attachments/assets/755c86ee-e445-4ea8-bc2c-cca85df48686' width='14px' height='14px' style='vertical-align: middle; margin-right: 4px;' /> **Build is starting...** 
 
             ⏰ Started at: ${{ steps.completion-time.outputs.time }} UTC