v0.2.0

• ota check --all: whole-network OTA firmware sweep. One
  device/ota_update/check round trip per device (coordinator and disabled
  devices skipped; --include-disabled overrides), sorted update-available-
  first. Each device is classified as update_available / up_to_date /
  not_supported / unknown / error — a dead device becomes an error row
  and never hides the rest of the network's firmware state. --with-update
  narrows to devices that actually have pending firmware, --timeout tunes
  the per-device round trip. Core functions check_all, summarize_check
  and _classify in core/ota.py. 25 new tests (unit + E2E + workflow).