Feat/stock provider adapter 8

[delfinacorr]

🚀 Neko Pull Request

Mark with an x all the checkboxes that apply (like [x])

• [ X ] Closes Implement first stock price provider adapter #8
• [ ] Added tests (if necessary)
• [ X ] Run tests
• [ X ] Run formatting
• [ X ] Evidence attached
• [ ] Commented the code

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📌 Type of Change

• [ ] Documentation (updates to README, docs, or comments)
• [ ] Bug fix (non-breaking change which fixes an issue)
• [ X ] Enhancement (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

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📝 Changes description

• The first external stock price provider was implemented for the Neko-Oracle-RWA system. I focused on establishing a solid and scalable foundation, not just the API connection.

• Selection of Finnhub: I decided to move forward with Finnhub for this POC due to its low latency for US market data and its clean response structure, ensuring that the oracle receives accurate information with minimal overhead.

• Architecture: I separated the StockService from the FinnhubAdapter, making the system vendor-agnostic. For example, if they need to change their API in the future, the core of the ingestor will remain unchanged.

• Data Normalization: I implemented a transformation layer that "hardens" the system. The adapter converts the raw response into a standardized object, enforcing numeric types and normalizing tickers to uppercase to prevent inconsistencies in the future database.

• Security: All credential management was integrated using environment variables (.env), ensuring that API keys are never leaked into version control.

• Monorepo Integration: I synchronized the types in @oracle-stocks/shared to ensure that the data contract is respected by all microservices in the Neko ecosystem.

📸 Evidence (A Loom/Cap video is required as evidence, we WON'T merge if there's no proof)

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⏰ Time spent breakdown

• Finnhub API Research: 20 min

• Adapter and Service Implementation: 45 min

• Monorepo Integration and Debugging: 30 min

• Total: ~1 hr 35 min

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🌌 Comments

• The implementation remains optimized according to the requirements of problem. No aggregation logic was added so that the proof of concept (POC) would focus on the data ingestion flow. It was a pleasure contributing to neko. Than you very much for the opportunity.!

[Villarley]

LGTM