fb6eae7fe2
Five governance + onboarding files that collectively close the "no high-level documentation outside of README" gap. - ARCHITECTURE.md: workspace layout, Indicator trait contract, per-indicator file conventions, numerical-stability notes, cross-crate flow diagram, navigation cheatsheet, deliberate non-goals, performance characteristics, stability commitments. - ROADMAP.md: north star, 0.3 / 0.4 / 0.5 release windows, indicator-wishlist intake rules, explicit non-goals, versioning policy. - CITATION.cff: GitHub-renders as "Cite this repository" button; enables academic adoption. - .github/FUNDING.yml: surfaces Sponsor button on the repo page. - .editorconfig: normalises indent/EOL across IDEs (Rust/Python 4 spaces, JS/TS/JSON/YAML/MD 2 spaces, Makefile tabs). Touches no Rust source, no CI workflows, no behaviour. Additive only. URLs in ROADMAP/CITATION already reference the post-transfer `wickra-lib/wickra` org so the files stay valid once the org migration in PR #59 lands; merge this PR only after #59 to keep main consistent.