Define the repository architecture corpus

[szmyty]

Summary

• adds the complete 18-document Aether architecture reference set
• defines renderflow's domain, provenance and rights boundaries, human and AI authority, system structure, experience language, decisions, and phased roadmap
• separates observed repository evidence from target capabilities and optional ecosystem integrations
• includes Mermaid views and a complete META inventory

Architecture source

Follows egohygiene/aether#42 and the Empathy reference corpus.

Validation

• 18 canonical documents with stable renderflow-* IDs
• resolved, acyclic dependency graph
• one H1 per file; relative links resolve
• META inventories every file and artifact ID

Review notes

Documentation only. No assets, resources, publications, rendering jobs, links, releases, or external services are changed.