The hcs library added a new Payload_too_large variant to the Websocket.error
type. Handle this case in the wb websocket server to fix exhaustive pattern
matching warning.

Release 0.1.1

- Add LICENSE (ISC) and README.md
- Add documentation: architecture, codecs, getting-started, json-joy-mapping
- Reorganize demo apps: wb (HCS), wbd (Dream), wbr (Raylib)
- Remove deprecated lib_eio and crdt-eio.opam
- Fix dune-project metadata (version 0.1.0, dedupe authors)
- Update code comments to reference issue tracker