[Enhancement] Implement Columns Utilities

[yasmramos]

Description

Add multi-column layout utilities for newspaper-style layouts.

Task

• Add columns-n utilities (columns-1 through columns-6)
• Add auto-columns utilities
• Add column-span utilities (span-all, span-none)
• Add break-inside utilities (break-inside-auto, break-inside-avoid)
• Test with text-heavy content

Files to modify

• src/main/resources/tailwindfx.css
• src/main/java/io/github/tailwindfx/Styles.java

Resources

• TailwindCSS Columns