W2: SZL Estate cross-link footer + honest status label

docs(README): fix dead holographic link + add receipt-cluster cross-links

README: estate cross-link alignment + clarity (Wave 1, T003)

docs: add Ouroboros Thesis concept DOI 10.5281/zenodo.19944926

feat(brand): add short_description; normalize off-brand color (green/indigo -> gray/yellow)

yarqa Space — FastAPI + vendored-THREE (docker SDK), honest CFD tier

initial commit