chore: Resolve several build warnings (#1076)

## Summary

* Resolve several build warnings

---

### AI Usage

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lib/Logging/Logging.h

@@ -68,4 +68,7 @@ class MySerialImpl : public Print {
   static MySerialImpl instance;
 };
 
-#define Serial MySerialImpl::instance
+#ifdef Serial
+#undef Serial
+#endif
+#define Serial MySerialImpl::instance

platformio.ini

@@ -35,6 +35,7 @@ build_flags =
 # Increase PNG scanline buffer to support up to 2048px wide images
 # Default is (320*4+1)*2=2562, we need more for larger images
   -DPNG_MAX_BUFFERED_PIXELS=16416
+  -Wno-bidi-chars
 
 build_unflags =
   -std=gnu++11
@@ -91,4 +92,3 @@ build_flags =
   -DCROSSPOINT_VERSION=\"${crosspoint.version}-slim\"
   ; serial output is disabled in slim builds to save space
   -UENABLE_SERIAL_LOG
-