core: implement loan credit scoring pipeline

[EmeditWeb]

Problem

Loan approval is currently manual. There is no
automated credit assessment.

What To Build

1. Create src/modules/credit-scoring/ module
2. Auto-approval / auto-reject / manual review rules
3. POST /loans/:id/assess endpoint

Files To Touch

• src/modules/credit-scoring/ (new)
• src/modules/loans/loans.service.ts
• src/modules/loans/loans.controller.ts
• supabase/migrations/[ts]_loans_under_review.sql

Acceptance Criteria

• Assessment runs automatically on loan creation
• Auto-approve works for qualified borrowers
• Auto-reject works for unqualified applications
• Manual review flagged for edge cases
• npm run build passes

Mandatory Checks Before PR

• npm run build passes
• No any types
• Unit tests for scoring logic
• PR references this issue

[ritik4ever]

Hi I’d like to work on this issue if it’s available. I’m a full-stack Web2 & Web3 developer with solid open-source experience and can start working on it right away.

[grantfox-oss]

🦊 GrantFox — @ritik4ever has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #31)
2. Your PR will be reviewed by the StepFi-app maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@ritik4ever's PR #46 was approved and merged by @EmeditWeb.

🏆 @ritik4ever: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (273 total points). Track your full progress on GrantFox.

👏 Great work, @ritik4ever! Keep contributing to StepFi-app.