test: add unit tests for src/utils/formatRemaining.ts (#1973)

[s6pa1rta3n-lab]

Description

Adds comprehensive unit tests for src/utils/formatRemaining.ts in src/utils/__tests__/formatRemaining.test.ts with 100% statement, branch, function, and line coverage. Also provides the pure utility function with typed MaturityStatus and RemainingMaturity interfaces.

Closes #1973

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Stipulations & Acceptance Criteria Checklist

• Pure utility function exports formatRemaining(maturityTimestamp, currentTimestamp)
• Matured state verified when diffMs <= 0 (text: 'Matured', status: 'matured')
• Critical threshold boundary covered (diffMs <= 1 day)
• Warning threshold boundary covered (1 day < diffMs <= 7 days)
• Healthy threshold boundary covered (diffMs > 7 days)
• Formatting branch days > 0 covered (${days}d ${hours}h ${minutes}m and 0h handling)
• Formatting branch days === 0 covered (hours omitted when zero, minutes only)
• Deterministic timestamp testing verified via optional currentTimestamp parameter
• Achieved 100% test coverage across statements, branches, functions, and lines

Checklist

• My code follows the code style and standards of this project (strict TypeScript, components/functions/constants naming conventions).
• I have performed a self-review of my code.
• I have commented my code, particularly in hard-to-understand areas.
• I have updated or added documentation where relevant (DEVELOPER_GUIDE.md, README.md, or inline files).
• I have added unit/integration tests that prove my fix is effective or that my feature works.
• Any new or modified logic has at least 95% test coverage (verified via pnpm run test:coverage or npm run test:coverage).
• I have ran the project linter (pnpm lint or npm run lint) and fixed all error diagnostics.
• I have verified that this change fits within the 96-hour campaign timeframe for contributor assignments.

Payout Routing

• EVM (Base/Arbitrum/Polygon/ETH): 0xF46C9F6d70C50BF81ef3588AB523a90a594a2F89
• Stellar: GCL6OXAMLD75BMTINA6EMRUDWK5THQUSHMYNLSNBCJAPZJHNYJTUNIBC

[vercel]

@s6pa1rta3n-lab is attempting to deploy a commit to the 1nonly's projects Team on Vercel.

A member of the Team first needs to authorize it.