Added inline script to cleanup dominant color CSS variable on image load

[Dhruval-678]

Summary

Fixes #2432

Changes

Added inline script to cleanup dominant color CSS variable on image load.
This script removes the --dominant-color CSS variable from images after they load,
preventing issues with dynamically loaded or lazily-loaded images.

Use of AI Tools

Clude code

[github-actions]

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Co-authored-by: Dhruval-678 <dhruval04@git.wordpress.org>
Co-authored-by: b1ink0 <b1ink0@git.wordpress.org>
Co-authored-by: mukeshpanchal27 <mukesh27@git.wordpress.org>
Co-authored-by: westonruter <westonruter@git.wordpress.org>

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 69.28%. Comparing base (8d1741e) to head (181ef03).

Files with missing lines	Patch %	Lines
plugins/dominant-color-images/hooks.php	0.00%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##            trunk    #2448      +/-   ##
==========================================
- Coverage   69.33%   69.28%   -0.06%     
==========================================
  Files          90       90              
  Lines        7749     7755       +6     
==========================================
  Hits         5373     5373              
- Misses       2376     2382       +6     

Flag	Coverage Δ
multisite	69.28% <0.00%> (-0.06%)	⬇️
single	35.70% <0.00%> (-0.03%)	⬇️

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[mukeshpanchal27]

Suggested change

	wp_register_script( 'dominant-color-cleanup', false, array(), DOMINANT_COLOR_IMAGES_VERSION, true );
	wp_register_script( 'dominant-color-cleanup', false, array(), null, true ); // phpcs:ignore WordPress.WP.EnqueuedResourceParameters.MissingVersion

IMO we don’t need to update the script version here. Versioning isn’t really necessary, and we can just pass null instead.

This is similar to how scripts are registered in the View Transitions plugin.

WDYT @westonruter

[westonruter]

Correct. It is an inline script, so the version is not used.

[westonruter]

The sniff should be updated to not earn when null is used for a script with a false src, but that's out of scope here.

[Dhruval-678]

@mukeshpanchal27
Requested changes has been applied.

Kindly have a look.