DESIGN.md is the reconciled high-level design after the 2026-09 restructure:
system context, roles, build-time composition, layers and dependency rules
(with the known exceptions), threading and event loop, end-to-end flows,
cross-cutting concerns and the upstream alignment policy. docs/adr/ holds the
nine decision records (ESP32 boot layout, S3 native USB, overlay precedence,
BLE privacy, Zephyr main pin, SX126x duty cycle and RX-busy gating, adaptive
contention window, storage backend, WiFi companion boards).
ARCHITECTURE.md stays the detailed component reference and links both.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
