Fold the CH390 overlay and NETWORK_PREFER_ETHERNET into
ThinkNode_M7_{repeater,room_server}_observer_mqtt and drop the separate
*_observer_mqtt_ethernet twins. The env names (and so the OTA manifests)
are unchanged, so existing M7 observers OTA into the Ethernet-preferred
image; without a cable they select stored Wi-Fi after a brief boot probe.
- Guard the boot-time link bootstrap to observer ESP32 builds. It ran
unconditionally in MyMesh::begin(), breaking every non-observer
repeater/room server build (ESP32 and nRF52).
- Rename NetworkInterface -> NetworkLink (class, accessor, files).
Arduino-ESP32 3.x ships its own NetworkInterface class and header,
which broke the ESP32-C6 builds. Drop WiFi.setAutoConnect(), a no-op
on 2.x and removed in 3.x.
- Refresh stored Wi-Fi credentials every bridge tick so the STA
reconnect loop picks up `set wifi.ssid` / `set wifi.pwd` without a
reboot, as the bridge did before the link moved out of it. Skip
reconnects while the SSID is empty.
- Restore the "WiFi connected: <ip>" / "WiFi disconnected: reason N"
debug lines the bridge used to print.
- Alert on Ethernet only once it has held a lease this boot or when no
Wi-Fi is configured; Wi-Fi-only installs of an Ethernet-preferred
image keep Wi-Fi alerts instead of reporting "Ethernet down".
- Record wifi.setup_complete only for Ethernet LAN onboarding, so
Wi-Fi builds keep the SSID-based first-boot portal rule.
- Use seq_cst for the route-switch lock/mutation flag handshake.
- Docs: SNMP RSSI sentinel is -127; describe link-return vs medium-switch
reconnect behavior accurately; note runtime credential pickup.
- Test: unknown keys inside a known /mqtt.json group are ignored, which
keeps wifi.setup_complete downgrade-safe.
The upstream/dev merge kept our side of variants/thinknode_m7/platformio.ini,
losing -D ENABLE_WIFI_INTERFACE and +<helpers/wifi/*.cpp>. Companion WiFi is
now gated on that flag, so the env built silently without WiFi.
Today if a user builds firmware with an incorrect WiFi SSID or password,
they get a generic `WiFi disconnected.` error message.
Extend logging to descirbe the reason that WiFi was disconnected.
I gathered the updated logs for the 3 scenarios below.
```
WiFi: Attempting manual WiFi reconnect...
WiFi: WiFi disconnected (reason=ASSOC_LEAVE). Flagging for reconnect...
WiFi: WiFi disconnected (reason=4WAY_HANDSHAKE_TIMEOUT). Flagging for reconnect...
WiFi: WiFi disconnected (reason=4WAY_HANDSHAKE_TIMEOUT). Flagging for reconnect...
WiFi: WiFi disconnected (reason=4WAY_HANDSHAKE_TIMEOUT). Flagging for reconnect...
```
```
WiFi: WiFi disconnected (reason=NO_AP_FOUND). Flagging for reconnect...
```
```
WiFi: WiFi connected successfully!
WiFi: Got connection
```
Payloads of 166 or 167 bytes previously passed the frame-sized bound
(MAX_CHANNEL_DATA_LENGTH = 167) but were rejected by sendGroupData
against MAX_GROUP_DATA_LENGTH (165), causing ERR_CODE_TABLE_FULL (retry
later) to be returned instead of ERR_CODE_ILLEGAL_ARG.
Fixes#3345
'custom:{}' (a DynamicConfigSerializer with nothing set) hits EXPECT_KEY
with a '}' and returns TOK_ERROR, so loadSerial stops there and silently
drops every property after it. Nothing follows 'custom' in NodePrefs
today, so it goes unnoticed until you add one.
Also include stdlib.h, which Arduino.h was providing on-device but not
in the native test build.
- scope the serial config CLI to RP2040; it was exposing the rescue CLI
(cat/rm/erase) on every ESP32 WiFi build, which gates it behind a
physical long-press
- bound and space out RP2040 rejoins: the core's join busy-waits, so cap
it at 5s and retry every 30s instead of every 10s
- stamp the reconnect timer in setup(), so the first loop() doesn't tear
down an association that is still finishing DHCP
- treat stored credentials as a pair, and pass NULL (not "") for an open
network
- teach build_as_lib.py where SerialWifiInterface moved
arduino-pico's WiFi.begin() blocks for up to 2x its 15s timeout, which
stalled the mesh loop on every reconnect attempt; use beginNoBlock().
Log the IP when the link comes up, and the status code when retrying.
agessaman