feat(rgba validation): allow floating point values for 0 and 1 on alpha channel

[Budaa]

Overview:
This pull request enhances the alpha value validation in the validateHTMLColorRgb function by allowing floating-point representations of 0.0 and 1.0. While the previous implementation already supported percentage values and general floating-point numbers, these updates ensure that the specific floating-point formats for 0 and 1 are explicitly accommodated.

Changes Made:

• Updated the regex pattern for the alpha channel to include:
  • Explicit support for 0.0 and 1.0, along with their variations (0.00, 1.00, etc.)

Detailed Changes:
The regex segment for alpha value validation has been refined to:

const A = '(\\/?${spaceNoneOrMore}(0?\\.?${digitOneOrMore}(%)?|1(\\.0+)?|0)${spaceNoneOrMore})?';

This update allows for:

• Floating-point representations like 0.0, 0.00, and 1.0, 1.00
• Retained support for percentage values (e.g., 50%, 100%)
• General floating-point values (e.g., 0.5, 0.75)

Testing:
The updated validation has been tested against various input cases to ensure its accuracy:

• Valid cases: 0, 0.0, 0.5, 1, 1.0, 50%, 100%
• Invalid cases: 1.1, -0.5, 200%, 1.01%

Impact:
This enhancement improves the robustness of the color validation logic by explicitly allowing floating-point representations of 0 and 1, ensuring better compliance with user expectations and CSS standards.

Conclusion:
I believe this update will significantly enhance the usability of the RGB color parsing utility. I look forward to any feedback and further improvements!