[CT-10] Write comprehensive unit tests for the reputation contract

[mftee]

Problem

The reputation contract's composite scoring formula (0-1000 scale combining rating, punctuality, and reliability) has no test coverage. An incorrect calculation would corrupt carrier rankings and shipper trust scores across the entire platform with no automated detection.

Proposed Solution

Write a test suite for the reputation contract inside contracts/package/tests/reputation/ that verifies the scoring formula with exact expected values.

Note: All work must be done inside the contracts/package/ directory. Do not modify any existing contract files outside this folder.

Acceptance Criteria

• Tests cover add_rating: valid scores 1-5 succeed; scores 0 and 6 return InvalidScore
• Tests cover composite score calculation with known inputs: e.g., avgRating=4, onTimePct=0.9, completionRate=0.95 → expected score calculated and asserted exactly
• Tests cover duplicate rating: same caller rating the same shipment twice returns DuplicateRating
• Tests cover get_reputation: returns the correct breakdown of all three score components
• Tests cover update_stats: on-time percentage updates correctly after new data
• All assert_eq! calls use explicit expected values, not computed values (tests verify the formula, not re-implement it)

[A6dulmalik]

@A6dulmalik has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I’d love to take this on by building a comprehensive test suite for the reputation contract’s scoring and validation logic.
I can add deterministic tests with explicit expected values for ratings, composite score calculations, duplicate protection, reputation breakdowns, and stats updates entirely within contracts/package/tests/reputation/.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @A6dulmalik to this issue.

[drips-wave]

Congratulations, @A6dulmalik! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @A6dulmalik: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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