Radio Galaxy FX rebrand build

Included in this package:
- Cosmic neon reskin based on the supplied icon/background pack
- Front-end + admin styled to match the new theme
- Branding changed from Radio Galaxy FX to Radio Galaxy FX
- Schedule/site station timezone changed to America/New_York (EST / USA label)
- Existing external temp admin auth file path was left unchanged on purpose so the current test login keeps working

Recommended follow-up:
- Create a new external auth folder/path for Radio Galaxy FX when you are ready, then update /admin/login.php and /admin/config/master_admin.php
- Review page copy in About / News / Team if you want fully bespoke Radio Galaxy FX wording on every page