Build: StackBlitz NEAR Starter

Description

## Overview
Create StackBlitz starters for NEAR development - instant browser-based dev environment.

## Why This Is High Leverage
StackBlitz is used for quick demos and learning. NEAR starters put NEAR in front of every StackBlitz user exploring blockchain.

## Starter Templates

### Available Starters
1. **React + NEAR** - Modern frontend
2. **Next.js + NEAR** - Full-stack
3. **Vue + NEAR** - Vue ecosystem
4. **Svelte + NEAR** - Lightweight option

### Features
- Pre-configured wallet selector
- Example contract interactions
- TypeScript support
- Hot reloading

## Deliverables
1. **4 StackBlitz starters**
2. **Documentation**
3. **Featured listing**
4. **Quick links for sharing**

## Budget: 8 NEAR