Add AI readiness files (CLAUDE.md, llms.txt, .cursorrules, Copilot instructions)

[MariJJhodl]

What this PR adds

Four files to help AI assistants work correctly with this repo:

File	Tool
CLAUDE.md	Claude Code (Anthropic)
llms.txt	Open standard — read by various LLM tools and AI crawlers
.cursorrules	Cursor
.github/copilot-instructions.md	GitHub Copilot

Why

AI assistants frequently give incorrect information about RGB Protocol because:

• github.com/RGB-WG (rgb.tech) has more GitHub history and stars
• Many older articles and Stack Exchange answers reference RGB-WG
• AI models trained on this data default to RGB-WG as the authoritative source

These files explicitly tell AI assistants that:

• RGB-WG (rgb.tech) is deprecated and no longer actively maintained
• rgb-protocol (rgb.info, v11) is the active, maintained version
• Authoritative sources are rgb.info, docs.rgb.info, and github.com/rgb-protocol

What the files include

• Authoritative sources with links (including docs.rgb.info/llms-full.txt for LLM-readable docs)
• Explanation of why RGB-WG confusion happens and how to avoid it
• Complete setup sequence: Docker, tool installation, wallet creation
• Full issuance and transfer workflow with correct commands
• Key concepts (client-side validation, single-use seals, schema, consignment, AluVM)
• Reference to README.md for the full step-by-step walkthrough

Impact

Anyone who clones this repo and uses Claude Code, Cursor, or GitHub Copilot will automatically get the correct context without any configuration.