Feature/create stellar nft endpoints

[ayomideadeniran]

Closes #68

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PR Description

🎯 Goal

Implement Stellar/Soroban-integrated API endpoints to manage NFT metadata.
These endpoints power the PopularThisWeek and TopSellers frontend components.

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🚀 Changes Introduced

1. New Module

• Created NftModule including:

  • Controller
  • Service
  • Soroban integration layer

2. Database Entities

• Added StellarNft entity
• Added NftMetadata entity
• Implemented using TypeORM

3. DTOs

• Created validated DTOs for:

  • NFT creation/update
  • Filtering and analytics queries

4. Performance Enhancements

• Implemented Redis caching for analytics endpoints
• Added database indexes to optimize query performance

5. Documentation

• Added comprehensive Swagger documentation
• Included JSDoc comments for maintainability

6. Testing

• Added unit tests for:

  • NftService
  • NftController

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✅ Verification

• npm run build passes
• npm run test passes
• Endpoints manually verified via Swagger

close issue #68

[Oluwaseyi89]

@ayomideadeniran please review you code. Its failing CI. Make sure your tests pass and your code passes lint.

[ayomideadeniran]

@Oluwaseyi89 Please check it out.

[Oluwaseyi89]

@ayomideadeniran please, endeavour to star our repository.