Fix Leafony AP03 PB5 pin mapping to D4

[taltalp]

Summary

Change the Leafony AP03 PB5 definition from 1 to 4.

In variant_LEAFONY_AP03.cpp, digitalPin[1] is PA_2 and digitalPin[4] is PB_5. However, the header defines PB5 as 1, so calls such as pinMode(PB5, ...) target PA2 (the default Serial TX pin) instead of PB5.

This one-line change makes the header consistent with the pin mapping table. PB5_ALT1 also inherits the corrected definition.

Validation

• Confirmed the incorrect mapping in upstream main at 21c906e95078b1a8ee5a5a68059cda1fc33945f0.
• Compared all 18 GPIO macros defined as numeric pin indices with digitalPin[]. PB5 was the only mismatch before the fix; all 18 match after the fix.
• Built the minimal sketch below with PlatformIO ststm32@19.3.0, Arduino STM32 Core 2.10.1, and the standard board = leafony_ap03 definition. Both static_assert checks failed before the fix. The same sketch built successfully after applying the one-line change to an isolated copy of the framework.
• Build validation used the released Core 2.10.1 with the same change applied. The full upstream main branch was not built, and GPIO behavior has not been tested on hardware. The runtime check in setup() was compiled but not executed.

#include <Arduino.h>

static_assert(PB5 == 4, "PB5 must refer to D4");
static_assert(PB5 != PA2, "PB5 must not alias PA2");

void setup()
{
  if (digitalPinToPinName(PB5) != PB_5) {
    while (true) {}
  }
  pinMode(PB5, INPUT);
}

void loop() {}

Code formatting

The change replaces a single digit and preserves the existing formatting. CI and AStyle results will be available in the PR checks.

[fpistm]

@taltalp
Please update all your comment in english.

[fpistm]

Thanks for the fix.