Documentation of Color names related to ECMA-48

[AvishekDas5]

Summary

Add comprehensive documentation explaining Windows Terminal's color naming scheme and relationship to ECMA-48 standards.

Problem Solved

Users are frequently confused by color names like brightBlack and brightWhite which seem contradictory at first glance. This documentation provides clear explanations and practical examples to resolve this confusion.

Changes Made

• Color reference table with all 16 color names, indexes, RGB values, and descriptions
• Practical usage examples including complete working color schemes
• Common questions section addressing specific confusion points like "Why is brightBlack not black?"
• Comparison table with .NET ConsoleColor enum for developers migrating from .NET
• Historical context explaining ECMA-48 standard background
• Step-by-step instructions for applying color schemes

Key Features

• User-first approach: immediate answers before background information
• Complete copy-paste examples for practical use
• Visual color swatches in reference table
• Conversion guide for .NET developers
• Addresses the main user confusion points identified in the issue

Validation

• Explains why brightBlack = dark gray (not contradiction)
• Clarifies white vs brightWhite distinction
• Provides practical JSON examples
• Includes complete working color scheme
• Addresses .NET ConsoleColor comparison request
• Follows user-focused documentation structure

Closes #2641

[AvishekDas5]

@microsoft-github-policy-service agree

[DHowett]

Thanks! We'll have to have a discussion internally to see how we feel about this and if it should be a public document rather than just one in the repository.

[AvishekDas5]

Hi! Just checking in on this. I understand you're having an internal discussion about where this documentation should live (repository vs Microsoft Learn). I'm happy to make any adjustments needed based on your decision. Please let me know if there's anything specific you need from me in the meantime. Thanks!