- add docs/explanation/kudos_accounting.md (design rationale and guarantees), docs/reference/kudos_accounting.md (maintainer contract: schemas, producer/consumer inventories, lock order, review checklist), and docs/how-to/kudos_ledger_operations.md (cutover, rollback, recovery procedure)
- add docs/README.md index and link it from the repository README
- add the haidra-assets submodule for shared user-facing kudos documentation
