Step-by-step operator guide for standing up an aborist mesh between
two real hosts: pre-flight, init/enable on both peers, out-of-band
pubkey exchange, mutual enrollment, mesh serve, mesh sync, audit
chain integrity checks, eviction protocol, reset/teardown.
Calls out what's not yet wired (mesh pull, per-peer chain merge,
AEAD body encryption) so operators don't expect features that ship
later. Pairs with docs/mesh.md (protocol contract) and the e2e tests
in tests/test_mesh_wire_e2e.py.
Adds docs/mesh.md and five graphviz diagrams covering the federation
layer: identity stack, epoch state machine, per-member secret envelope,
gossip wire contract, and operator decision tree. Pins the protocol
contract for the upcoming HTTP wire (mesh sync, mesh serve).
Makefile gets a 'docs' target with pattern rule so PNG renders are
incremental from .dot sources.
