Build MCP Server: NEAR Account & Transaction Explorer

Description

## Overview
Create an MCP server that lets Claude explore NEAR accounts, transactions, and on-chain activity - essentially bringing block explorer functionality into AI conversations.

## Why This Matters
Users often need to check transaction status, account history, or understand what happened on-chain. Claude should be able to look this up and explain it.

## Technical Requirements

### MCP Tools
```typescript
// 1. get_account_info
// Comprehensive account information
// Input: { account_id: string }
// Output: { balance, storage, created_at, num_transactions }

// 2. get_transaction_history
// Recent transactions for an account
// Input: { account_id, limit?: number }
// Output: Array of { tx_hash, type, timestamp, counterparty, amount }

// 3. get_transaction_details
// Full transaction details with human-readable explanation
// Input: { tx_hash: string }
// Output: { actions, receipts, outcome, gas_used, explanation }

// 4. search_accounts
// Find accounts by pattern or criteria
// Input: { pattern?: string, has_contract?: boolean }
// Output: Array of matching accounts

// 5. get_token_balances
// All fungible token balances for an account
// Input: { account_id: string }
// Output: Array of { token, balance, usd_value }
```

### Data Sources
- NEAR RPC for real-time data
- NEAR Indexer/Explorer API for historical data
- Price feeds for USD values

## Deliverables
1. **MCP server** with explorer functionality
2. **Human-readable transaction explanations**
3. **Published to npm and MCP Registry**
4. **Documentation with use cases**

## Budget: 10 NEAR