Add unit tests for all utility functions in `frontend/src/utils/`

[Mystery-CLI]

🔧 Title: Add unit tests for all utility functions in frontend/src/utils/

📘 Description
frontend/tests/utils.test.js exists but only covers some utilities. validateStellarAddress.js, formatBalance.js, validateAmount.js, errorMessages.js, and searchHighlighter.js need comprehensive unit tests including edge cases.

✅ Acceptance Criteria

• Achieve 100% branch coverage for all files in frontend/src/utils/
• Add tests for: empty string, null, undefined, max/min values, special characters
• Add property-based tests using fast-check for validateAmount and formatBalance
• All tests must run in under 1 second total

🔧 Context: frontend/src/utils/; frontend/tests/utils.test.js.

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[nanaabdul1172]

@nanaabdul1172 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer I would love to work on this issue
Kindly assign

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[whitezaddy]

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

I can resolve this issue accurately and precise within the hour. Please assign it to me

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[kingdavid0016]

@kingdavid0016 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi I'm a full stack developer I'll like to work on this issue because It picks my interest and Ive got experience with similar projects I'll have it solved in 24 hours or less

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[Gadflyxx]

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

i would love to work on this issue maintainer

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[drips-wave]

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

🧑‍💻 @Gadflyxx: 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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