Protect and Rate Limit the Smart Contract Address Shortener API

[yusuftomilola]

Secure the API by enforcing authentication and rate limiting to prevent abuse.

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✅ Tasks

• Add JWT authentication middleware to protect the POST /shorten endpoint
• Implement rate limiting per user or IP address
• Log API usage for analytics and monitoring
• Write tests verifying auth enforcement and rate limiting

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📌 Acceptance Criteria

• ✅ Auth middleware restricts access to authorized users only
• ✅ Rate limiting prevents excessive usage per user/IP
• ✅ API logs capture relevant usage data

[shamoo53]

hi, i would like to work on this issue,
kindly assign