1. REMOVED auto-save entirely
   - No more saving on every keystroke
   - Changes tracked as 'dirty' state

2. NEW: Sticky bottom save bar
   - Shows 'No unsaved changes' (grey) / '⚠️ Unsaved changes' (yellow)
   - '💾 Save All' button only active when changes exist
   - Success: '✓ Saved!' feedback
   - beforeunload warning if leaving with unsaved changes

3. Image uploads now go to Supabase Storage
   - Uploaded to: profile-images/branding/{slot}.{ext}
   - Public URL stored in platform_assets table
   - Survives deploys (not local filesystem)
   - Also saved locally for immediate preview in admin
   - Asset URL returned by /api/branding.php GET endpoint

4. Player app reads asset URLs from Supabase
   - theme.js fetches /api/branding.php → includes assets from platform_assets
   - Uploaded SVGs/PNGs render at exact specified size
   - object-fit:contain + image-rendering for no pixelation

Flow:
- Admin uploads logo.svg → Supabase Storage → URL in platform_assets
- Admin changes gold color → marks dirty → clicks Save → Supabase platform_theme
- Player loads app → /api/branding.php → gets colors + asset URLs → applies
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>