## Summary
- Add `image_utils.ts` for extracting MIME type and extension from image
data (base64 or binary)
- Add `image_dimension_utils.ts` for reading dimensions from
PNG/JPEG/GIF/WebP images
- Update `web_crawl` to use `maxTokens` (9000) from
`GEMINI_CRAWL_LONG_CONTEXT` config
- Update `prepare_step_utils` to handle `GEMINI_CRAWL_LONG_CONTEXT`
model config
- Add comprehensive tests for all new utilities

## Test plan
- [x] All existing tests pass
- [x] New tests added for image utilities covering:
- Image type detection from various formats (PNG, JPEG, GIF, WebP, BMP,
TIFF)
  - Base64 and binary data handling
  - Invalid/corrupted data handling
  - Dimension extraction from PNG, JPEG, GIF, WebP

🤖 Generated with [Claude Code](https://claude.com/claude-code)
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---------
Co-authored-by: Will Chen <willchen90@gmail.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>