Version 2 - Stage 2 Branding & Background Manager

This stage keeps the original user UI/dashboard layout and adds:

1. User background upload from Admin Settings.
2. Fixed / Random / Slideshow background modes.
3. Sample HD-style backgrounds included in /assets.
4. Main card logo upload replacing “YOUR LOGO HERE”.
5. Background logo upload on the left-side background area.
6. Editable background logo text line 1 and line 2.
7. Editable bottom background text.
8. Three option image upload slots on the user card.
9. Uploaded option images auto-fit inside the existing IMG boxes and are not clickable.
10. Preview User Page link from Admin Settings.

Install/update notes:
- Upload all files to hosting.
- Make sure /uploads is writable, usually permission 755 or 775.
- Import schema.sql if this is a new install.
- Existing installs can keep using the app; missing settings are created when saved from Admin Settings.
