Fix misplaced Outer/Inner names when using named() on Each

[alganet]

The Each validator was using "Outer" names (the name applied to the parent) in child results and vice-versa.

This commit fixes it, and also streamlines the Result class, introducing helper mapChildren and mapAdjacent methods and removing unecessary recursive array_maps.

Named children now also display their names, allowing users to create more meaningful messages that do not spam nested .0....0...etc numeric keys which could be confusing. If the user does not name them, the previous behavior is kept.

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This fixes #1639

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.14%. Comparing base (b69beb1) to head (04fe1d0).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1640      +/-   ##
============================================
+ Coverage     98.03%   98.14%   +0.11%     
- Complexity      961      963       +2     
============================================
  Files           197      197              
  Lines          2234     2213      -21     
============================================
- Hits           2190     2172      -18     
+ Misses           44       41       -3     

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[Copilot]

Pull request overview

This PR fixes a bug where the Each validator was inverting Outer and Inner names when using named(), and also refactors the Result class for better maintainability.

Changes:

• Fixed Each validator to correctly apply Outer names to the parent result and Inner names to child results
• Refactored Result class by introducing mapChildren and mapAdjacent helper methods
• Enhanced message formatting to show named children with their names (e.g., .0 (<- Inner)) while avoiding redundancy in nested displays

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/feature/Validators/EachTest.php	Updated test expectations to match corrected naming behavior where Outer names apply to parent "Each item in..." messages and Inner names apply to individual child items
src/Validators/Each.php	Added withPrecedentName(false) to child results and removed incorrect withNameFrom call to fix name inversion
src/Validators/Core/FilteredNonEmptyArray.php	Removed incorrect withNameFrom calls that were propagating child names to parent error results
src/Result.php	Refactored with new withPrecedentName method, streamlined name/path handling, and added mapChildren/mapAdjacent helpers to eliminate redundant array_map calls
src/Message/Formatter/NestedArrayFormatter.php	Enhanced to conditionally remove redundant names from children when they match the parent name in nested displays
src/Validators/Key.php	Code formatting improvement (line break added for readability)

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[henriquemoody]

Awesome work, and great catch! I think we should get to an agreement regarding the withInput() before merging this one, though.

[henriquemoody]

I have only a nitpick comment, but I'm approving