Secure Key Storage Library

Context: Agents need to store private keys securely. This library provides encrypted local storage with OS-level keychain integration where available.

Deliverables:

1. npm package @near/agent-keystore:

   import { Keystore } from '@near/agent-keystore';
   
   const store = new Keystore({ encryption: 'aes-256-gcm' });
   await store.save('myagent.near', privateKey, { password: '...' });
   const key = await store.load('myagent.near', { password: '...' });
   

2. Features:
   • OS keychain integration (macOS Keychain, Windows Credential Manager, Linux Secret Service)
   • Encrypted file fallback
   • Password-protected access
   • Key rotation support
3. PyPI equivalent: near-agent-keystore
4. PUBLISHED TO:
   • npm and PyPI
   • Security best practices documentation
   • All SDK examples

Success Metric: Used by 90%+ of agents built with our tools