feat: Export isClientEnvironment function

[Lee-WonJun]

Description

Extract the client-environment check into a new, exported isClientEnvironment() helper so tests can mock it directly, without changing any runtime behavior or throwing errors.

As this is not intended as a patch but rather a small enhancement, I avoided adding any breaking behaviors like throwing errors to ensure full backward compatibility.

Related Issue: #178

Changes

• Add and export isClientEnvironment() util
• Have useClientLayoutEffect call it and return early when false (non-changed behavior)
• No other logic or error-throwing changes—existing behavior is untouched

Motivation and Context

// jest.setup.js
global.navigator = { product: 'ReactNative' };

Patching global.navigator in jest.setup.js is a pretty good workable solution, but it feels a bit weird and like a global workaround.

By extracting and exporting the check, we enable targeted jest.mock()/jest.spyOn() of exactly that function (and it makes the [overlay-kit] repo itself more testable)

While I’m not primarily a frontend engineer and may not be fully familiar with the canonical idioms, I believe this small suggestion maintains full backward compatibility, introduces no runtime changes, and allows for more flexible testing.

How Has This Been Tested?

I didn’t find dedicated tests for this hook, so I’ll check the CI test results after opening the PR.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have performed a self-review of my own code.
• My code is commented, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.

Further Comments

[changeset-bot]

🦋 Changeset detected

Latest commit: 2c7a142

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
overlay-kit	Patch

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Name	Status	Preview	Comments	Updated (UTC)
overlay-kit	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jun 17, 2025 2:53pm

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.85%. Comparing base (6d35a52) to head (2c7a142).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #179   +/-   ##
=======================================
  Coverage   99.85%   99.85%           
=======================================
  Files          15       15           
  Lines        1337     1340    +3     
  Branches      260      262    +2     
=======================================
+ Hits         1335     1338    +3     
  Misses          2        2           

Components	Coverage Δ
overlay-kit	99.85% <100.00%> (+<0.01%)	⬆️

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[jungpaeng]

Thank you for your suggestion.
However, since this PR does not completely resolve the issue, I’ve updated the description to ensure the issue is not closed.

[Lee-WonJun]

Understood. Thanks for updating it directly.