refactor(mergeProps): mergeProps by removing redundant undefined check and simplifying style merging logic

[wo-o29]

Overview

This PR improves the mergeProps utility function by:

1. Removing redundant checks for undefined in the pushProp function.
   Since the if (curr[key] === undefined) continue; statement is already handled at the start of the loop, the additional else if (curr[key] !== undefined) check inside the default case is unnecessary and removed for clarity.

2. Simplifying the mergeStyle function by removing the null check for the first style argument.
   In practice, a is never null but can be undefined.
   Spreading potentially undefined values with { ...a, ...b } safely results in identical behavior without extra branching logic.

These changes clean up the code, improve maintainability, and have no effect on the existing behavior or output of the utility.

Checklist

• Did you write or update tests to cover your changes?
• Did you run yarn run fix to format and lint the code and docs?
• Did you run yarn run test:coverage to confirm test coverage?
• Did you update JSDoc comments if applicable?

[Copilot]

Pull Request Overview

Refactors the mergeProps utility function by simplifying conditional logic and removing redundant checks for better maintainability.

• Removes redundant undefined check in the default case since it's already handled at the loop start
• Simplifies style merging by removing null check and relying on spread operator behavior
• Improves code clarity without changing functionality

Comments suppressed due to low confidence (1)

src/utils/mergeProps/mergeProps.ts:53

• The break statement on line 50 creates unreachable code on line 53. When mergedFunction is truthy, the code will exit the switch case and never reach the assignment prev[key] = curr[key]. Consider restructuring this logic or removing the unreachable code.

        const mergedFunction = mergeFunction(prev[key], curr[key]);

        if (mergedFunction) {
          prev[key] = mergedFunction;
          break;
        }

        prev[key] = curr[key];

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (5bdb4ff) to head (d62a553).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #279   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files           37        37           
  Lines         1093      1092    -1     
  Branches       324       323    -1     
=========================================
- Hits          1093      1092    -1     

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