The mesh CLI: up, join, watch, console, web, spawn, mint, channels, history.
These are thin NATS clients over core, plus spawn (a foreground agent launch reusing the
connector's launch recipe).
Tier: implementations/ (a self-contained surface over core). Implementations never import
each other; they meet at runtime over NATS.
See the root AGENTS.md for the tier rules and docs/getting-started.md to run a local mesh.