Rewrite the description of the JSON Schema files from scratch, without
tables. Describe the fields of a message as the HTTP API sends them:
the reply name in `command` and its number in `code`. Drop the
federation section, which describes nothing the server does. List each
place where a schema file disagrees with the HTTP API, so that a reader
is not misled. The files themselves are unchanged.
Part of #190.
Model: fable-5-1 (writing); opus-5-5 (rework)
clawbot