- Use PNG format instead of JPEG for transparency support
- Non-strict mode only resizes if image width > target width
- Replace CATALOGUE_BACKGROUND_IMAGES_COLOR with CATALOGUE_BACKGROUND_IMAGES_RGBA (tuple default (0,0,0,0))
- Move all inline imports to top of test file
- Add test_resize_non_strict_no_upscale test case
- Add comment explaining settings.DEBUG guard for media serving
- Add CatalogueImage model with FK to Product
- Add image resize service (strict/non-strict modes with configurable dimensions)
- Add CRUD API endpoints with admin-only write permissions
- Add catalogue_images field to product listing/detail endpoints
- Serve media files in development via static()
- 28 TDD tests covering model, API, permissions, resize, and product listing
