Resolve conflicts: keep both Ethernet CLI and SenseCAP power-off
button code in repeater, keep both Ethernet docs and power management
CLI docs.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The Ethernet retry loop in repeater and room server checked
hardwareStatus() and linkStatus() before calling Ethernet.begin(),
which always returned EthernetNoHardware since hardware detection
only happens during begin(). Extract shared Ethernet CLI code into
EthernetCLI.h to prevent future divergence. Also fix time_t type
mismatch in companion radio Ethernet init.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>