v0.11.0

Added

• inbox: a global, threaded, durable log for agent-to-agent messages.
  (#169) inbox post --thread <id> --from <name> --note <text> appends to
  <plugin state dir>/inbox/<thread-id>.ndjson; inbox read --thread <id>
  replays a thread in order; inbox search <query> substring-matches across
  every thread. Fleet-wide rather than scoped to one repository, and pull-only
  — there is no watch or subscribe, and it is not wired to SendMessage or any
  other live channel, deliberately: an agent that wants a message durable
  calls both. No retention yet; append-only.