Update OASIS website: Redesign with LayerZero/Quantum Street inspired layout

- Redesigned homepage with clean, minimal aesthetic (no emojis)
- Added rotating carousel for use cases in hero section
- Updated principles section (changed Immutable to Zero Downtime)
- Enhanced ecosystem section with provider logos (5 columns)
- Added all provider logos: blockchain, cloud, storage, network providers
- Fixed logo alignment and spacing
- Improved card styling with hover effects and gradients
- Added monotone overlay effects for logos
- Moved Miden, Zcash, Aztec to top row
- Inverted Arweave and ThreeFold logos for better visibility

Author: maxgershfield