[Bug][Contract] RemittanceNFT::apply_score_delta bounds scores to 0 violating MIN_CREDIT_SCORE invariant

[blurbeast]

Issue #44

RemittanceNFT::apply_score_delta Bounds Scores to 0 Instead of Protocol Minimum (300)

• Title: [Bug][Contract] RemittanceNFT::apply_score_delta bounds scores to 0 violating MIN_CREDIT_SCORE invariant
• Labels: bug, contracts, medium
• Location: contracts/remittance_nft/src/lib.rs:803
• Description:
  apply_score_delta computes:

  let bounded_score = next_score.clamp(0, Self::MAX_SCORE as i64);

  decrease_score enforces Self::MIN_CREDIT_SCORE (300). Clamping to 0 allows negative score deltas to reduce borrower credit scores below the protocol-wide floor.
• Impact:
  Credit scores can drop to 0, violating credit scoring tier assumptions across lending contracts and backend scoring engines.
• Suggested Fix:
  Clamp next_score to [Self::MIN_CREDIT_SCORE as i64, Self::MAX_SCORE as i64].

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[Emelie-Dev]

@Emelie-Dev has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I would love to work on this issue

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[TheDEV111]

@TheDEV111 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi pls can I work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @TheDEV111 to this issue.

[drips-wave]

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