Suspend failed ESP32 MQTT and NTP uplinks for power saving

Share one bounded WiFi outage and recovery schedule across MQTT, automatic NTP, Companion station ownership and WebConfig. Preserve enabled settings and foreground access while allowing normal sleep after confirmed physical shutdown.

Honor failed SDK client stops before handing off WiFi, protect clean teardown and reconfiguration, and retry transient ESP-NOW channel restoration without repeated disconnects. Add production-method, SDK failure and real sleep regressions to CI.

Validation: native MQTT/NTP/clock/reconnect suites; production power and wrapper failure tests; browser, room HTTP, OTA and combined bridge regressions; Full Heltec V4 repeater, room and companion builds with capability, flash and linked-memory checks.

docs/WiFi.md

@@ -102,6 +102,32 @@ best effort rather than durable storage. Each enabled slot publishes
 independently, so one failed broker does not intentionally stop the other
 slots.
 
+## Automatic network outage power saving
+
+ESP32 MQTT firmware uses one shared outage timer for MQTT and NTP. If no broker
+demonstrates a working connection for five minutes, the MQTT worker stops its
+clients and NTP request before suspending background WiFi. Saved WiFi and broker
+settings remain enabled. Failed requests, a WiFi association, and NTP replies
+alone do not restart the outage timer or keep a failed MQTT uplink awake.
+
+After 30 minutes, the firmware opens a recovery window lasting up to two
+minutes. A broker acknowledgment or a connection that stays up for 30 seconds
+returns the node to normal operation. Otherwise WiFi is suspended for another
+30 minutes. An explicit management request can ask for an earlier probe.
+Automatic NTP requests have a 15-second timeout; failed requests wait 30 minutes
+instead of repeatedly running a blocking server search. Successful NTP retains
+the daily refresh schedule.
+
+Active browser administration, setup/OTA access points, connected Companion
+clients, and an attached WiFi OTA seeder protect their network access. An idle
+WebConfig listener does not prevent the cooldown. An enabled SNMP agent keeps a
+working LAN connection available. ESP-NOW keeps its radio and channel; only the
+failed infrastructure connection is suspended. LoRa continues operating, and
+when CPU power saving is enabled, its normal sleep eligibility returns after
+background WiFi shuts down. USB console and logging sleep rules still apply
+separately. This policy does not automatically turn off working services or
+expire an active setup access point.
+
 See [MQTT_IMPLEMENTATION.md](https://github.com/mikecarper/MeshCore/blob/keymindCascade/MQTT_IMPLEMENTATION.md) for the complete preset
 list, custom broker configuration, topic formats, authentication, diagnostics,
 and memory limits.