Exclude oversized RAK4631 repeater from LoRa OTA

tools/mota/pio_endf.py

@@ -28,11 +28,15 @@ import motalib as ml
 
 
 def _ota_enabled() -> bool:
+    disabled = False
+    enabled = False
     for d in env.get("CPPDEFINES", []):  # noqa: F821
         name = d[0] if isinstance(d, (list, tuple)) else d
+        if name == "DISABLE_LORA_OTA":
+            disabled = True
         if name == "ENABLE_OTA":
-            return True
-    return False
+            enabled = True
+    return enabled and not disabled
 
 
 def _is_nrf52() -> bool:

variants/rak4631/platformio.ini

@@ -48,6 +48,7 @@ lib_deps =
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
+  -D DISABLE_LORA_OTA=1                  ; Cascade repeater image exceeds the safe nRF52 in-place OTA ceiling
   -D DISPLAY_CLASS=SSD1306Display
   -D ADVERT_NAME='"RAK4631 Repeater"'
   -D ADVERT_LAT=0.0
@@ -59,7 +60,7 @@ build_flags =
 ;  -D MESH_DEBUG=1
 build_src_filter = ${rak4631.build_src_filter}
   +<helpers/ui/SSD1306Display.cpp>
-  ; OTA (ENABLE_OTA + flash store + EndF + helpers/ota) is inherited from the [rak4631] base now
+  ; The OTA sources remain inherited, but build.sh removes ENABLE_OTA for this oversized role.
   +<../examples/simple_repeater>
 
 [env:RAK_4631_repeater_bridge_rs232_serial1]