Migrate 19.5 MB of committed binary assets to Git LFS or CDN

## Recommendation

### 🗂️ CRITICAL: Migrate Large Binary Assets

Three large files are committed directly to git, bloating every clone by ~19.5 MB:

| File | Size | Notes |
|------|------|-------|
| `src/lib/litegraph/imgs/webglstudio.gif` | **12 MB** | Legacy litegraph demo asset — likely not needed |
| `src/platform/cloud/onboarding/assets/videos/video.mp4` | **6.5 MB** | Onboarding video |
| `public/assets/images/civitai.svg` | **1.5 MB** | Unusually large SVG |

## What Was Found

Git LFS is installed (`git-lfs/3.5.1`) but these files are tracked in regular git, not LFS. Every `git clone` downloads all 19.5 MB regardless of whether the files are needed.

## How to Fix

1. **Remove `webglstudio.gif`** if it's not used (it's a legacy litegraph demo image)
2. **Migrate remaining files to Git LFS**:
```bash
git lfs track '*.mp4' '*.gif'
git lfs migrate import --include='src/platform/cloud/onboarding/assets/videos/video.mp4,public/assets/images/civitai.svg'
```
3. Or move to a CDN and reference by URL

## Impact

Faster clones for all contributors and CI runs.

---
**Category:** Git Hygiene | **Priority:** Critical | **Effort:** Medium (~2 hr, may require history rewrite)
Part of #11022
_Filed by repo-audit skill_

┆Issue is synchronized with this [Notion page](https://www.notion.so/Issue-11025-Migrate-19-5-MB-of-committed-binary-assets-to-Git-LFS-or-CDN-33e6d73d3650814d9ba7e8669728fe7c) by [Unito](https://www.unito.io)

Start by checking references to src/lib/litegraph/imgs/webglstudio.gif, src/platform/cloud/onboarding/assets/videos/video.mp4, and public/assets/images/civitai.svg, then inspect the repository's current Git LFS configuration and history. Confirm whether the legacy GIF is unused and choose between LFS and CDN with maintainers. Done means the unnecessary asset is removed or migrated, references still work, and clone history no longer carries the large regular-Git blobs.

Written by the indexing model from the issue text.