Description

src/validators/amountValidator.ts has unit tests but no property-based coverage. Add fast-check properties that fuzz fractional precision, leading zeros, and negative sentinels so we catch silent regressions.

Requirements and Context

• Use fast-check as a devDependency
• Property: any input with >7 fractional digits must reject
• Property: integer-equivalent inputs round-trip
• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested Execution

1. Fork the repo and create a branch

   git checkout -b task/amount-validator-pbt

2. Implement changes
   • src/validators/amountValidator.test.ts
   • package.json
3. Test and commit
   • npm test -- amountValidator
   • Cover edge cases (denormalized numbers, NaN strings)
   • Include test output and notes in the PR

Example commit message

test: property-based coverage for amount validator

Acceptance Criteria

• At least four fast-check properties pass
• Runtime under 5s
• No flaky seeds
• Docs updated

Guidelines

• Backend (Node/TS): Jest, minimum 90% coverage
• Clear documentation and inline comments
• Timeframe: 96 hours