Fix build on Pico W

Use `lib_ldf_mode=chain+` so the LDF evaluates preprocessor conditions
when scanning for library dependencies. Without this, the LDF (in
default 'deep' mode) ignores it to find #include <BLEDevice.h> inside
the #ifdef ESP32 block in esp32/BLELogInterface.h, pulling in the
Arduino-Pico BLE library. That library only compiles correctly when
PIO_FRAMEWORK_ARDUINO_ENABLE_BLUETOOTH is set (which enables the
required BTstack defines), so without that flag the build fails. chain+
prevents this by honouring the #ifdef ESP32 guard.

examples/simple_repeater/main.cpp

@@ -2,7 +2,13 @@
 #include <Mesh.h>
 
 #include "MyMesh.h"
-#include <helpers/BLELogInterface.h>
+#if BLE_PACKET_LOGGING
+  #if defined(NRF52_PLATFORM) || defined(ESP32)
+    #include <helpers/BLELogInterface.h>
+  #else
+    #error "BLE_PACKET_LOGGING is not supported on this platform (only ESP32 and nRF52)"
+  #endif
+#endif
 
 #if MESH_PACKET_LOGGING && BLE_PACKET_LOGGING && (defined(NRF52_PLATFORM) || defined(ESP32))
   static BLELogInterface ble_log;

examples/simple_room_server/main.cpp

@@ -2,7 +2,13 @@
 #include <Mesh.h>
 
 #include "MyMesh.h"
-#include <helpers/BLELogInterface.h>
+#if BLE_PACKET_LOGGING
+  #if defined(NRF52_PLATFORM) || defined(ESP32)
+    #include <helpers/BLELogInterface.h>
+  #else
+    #error "BLE_PACKET_LOGGING is not supported on this platform (only ESP32 and nRF52)"
+  #endif
+#endif
 
 #if MESH_PACKET_LOGGING && BLE_PACKET_LOGGING && (defined(NRF52_PLATFORM) || defined(ESP32))
   static BLELogInterface ble_log;

variants/rpi_picow/platformio.ini

@@ -26,6 +26,15 @@ build_src_filter = ${rp2040_base.build_src_filter}
   +<PicoWBoard.cpp>
   +<../variants/rpi_picow>
 lib_deps = ${rp2040_base.lib_deps}
+; Use chain+ so the LDF evaluates preprocessor conditions when scanning for
+; library dependencies. Without this, the LDF (in default 'deep' mode) ignores
+; #ifdef guards and follows all #include directives unconditionally. That causes
+; it to find #include <BLEDevice.h> inside the #ifdef ESP32 block in
+; esp32/BLELogInterface.h, pulling in the Arduino-Pico BLE library. That
+; library only compiles correctly when PIO_FRAMEWORK_ARDUINO_ENABLE_BLUETOOTH is
+; set (which enables the required BTstack defines), so without that flag the
+; build fails. chain+ prevents this by honouring the #ifdef ESP32 guard.
+lib_ldf_mode = chain+
 
 [env:PicoW_repeater]
 extends = rpi_picow