Fix admin color fallback for PHP 8

[Davesaggio]

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[Davesaggio]

Summary

This fixes a PHP 8 fatal error in qtranxf_get_user_admin_color() when the current user does not have a valid admin color scheme available in $_wp_admin_css_colors.

Previously the code assumed this entry always existed and directly accessed:

$_wp_admin_css_colors[ $user_admin_color ]->colors

For non-admin users or unauthenticated/ajax contexts this could trigger a 500 error.

Fix

• validate that the selected admin color exists
• validate that ->colors exists and is an array
• fall back to fresh when the user color is missing/invalid
• return an empty array as a final safe fallback

Notes

Verified with php -l.