Full Theme Integration Completed

Added:
- assets/css/overlay_full_themes.css
- assets/js/overlay_theme_loader.js
- assets/js/director_theme_control.js
- api/theme_state.php
- data/theme_state.json

Themes:
- Gold Premium
- IPL Neon
- ICC Clean
- Sri Lanka Gold
- Red Fire
- Green Stadium
- Purple Night
- Clean Glass
- Glass Premium

Usage:
- Open director/dashboard page.
- Use 'Overlay Colour Theme' card.
- Click Apply Theme.
- OBS overlay auto-updates within ~1 second.

If your hosting blocks writing to /data, set folder permission to writable.
