The single/multi/hybrid 'deployment shape' was a misnomer: these keys only
affect the gateway (the one entrypoint supplying a runtime user ID), and the
three preset names stamped a lossy taxonomy onto three orthogonal knobs while
hiding which keys got written.
Replace it with an intent-led tree gated on gateway detection:
- _gateway_platforms() lazily inspects the gateway config (best-effort, no
hard dependency); the step auto-skips when no platform is connected.
- 'who talks to this?' → just me / me+others (pooled?) / only others, deriving
pinUserPeer + userPeerAliases + runtimePeerPrefix and echoing the result.
- [e] drops to a raw-knob editor for power users.
- The single→multi orphan guard survives as a pooling steer.