MQTT client proxying (#2587)

* WIP on MQTT proxy message queue

* Fix copy paste goof

* Progress on uplink

* Has packets

* Avoid trying to connect if we're proxying

* Pointer correctly

* Remove wifi guards

* Client proxy subscribe

* Fixed method that got bababababorked somehow... personally I blame CoPilot

* Short circuit logic

* Remove canned settings

* Missed some stuff in the move

* Guard pubsub client for non-networked variants

* Has networking guard

* else

* Return statement for fall-thru

* More gaurd removals

* Removed source filters. No wonder I was confused

* Bounding

* Scope guard around else and fix return

* Portduino

* Defs instead

* Move macro up to actually fix portduino

* Size_t

* Unsigned int

* Thread interval

* Protos

* Protobufs ref

arch/stm32/stm32wl5e.ini

@@ -13,7 +13,7 @@ build_flags =
   -DVECT_TAB_OFFSET=0x08000000
   
 build_src_filter = 
-  ${arduino_base.build_src_filter} -<platform/esp32/> -<nimble/> -<mesh/api/> -<mesh/http/> -<modules/esp32> -<mesh/eth/> -<mqtt/> -<input> -<buzz> -<modules/Telemetry> -<platform/nrf52> -<platform/portduino> -<platform/rp2040>
+  ${arduino_base.build_src_filter} -<platform/esp32/> -<nimble/> -<mesh/api/> -<mesh/http/> -<modules/esp32> -<mesh/eth/> -<input> -<buzz> -<modules/Telemetry> -<platform/nrf52> -<platform/portduino> -<platform/rp2040>
 
 board_upload.offset_address = 0x08000000
 upload_protocol = stlink