Add iBeacon example for ESP32

[colemancda]

Adds new ESP32 example that advertises as an iBeacon in addition to its name and address.

Also adds some Swift wrappers for the ESP32 SDK and NimBLE.

[erhankur]

@colemancda In my opinion, blink example should be left to just blink, as intended by its nature. You could consider creating a separate Bluetooth example.

[colemancda]

@erhankur I moved the example to its own and removed the blink code.

[erhankur]

@colemancda Thank you for the nice work!

I didn't play with bluetooth examples before. Just wanted to build to see if there is an issue.

Warnings regarding macro redefinitions ;

 warning: 'MYNEWT_VAL_BLE_SVC_GAP_DEVICE_NAME' macro redefined
 warning: 'MYNEWT_VAL_BLE_L2CAP_COC_MAX_NUM' macro redefined
 ... 

Probably you will need to cleanup BringingHeader.h .Removing #include "esp_nimble_cfg.h" fixes the warnings.

And error;

esp32-ibeacon-sdk/main/String.swift:12:15: error: could not find module 'Darwin' for target 'riscv32-none-none-eabi'; found: arm64-apple-macos, arm64e-apple-macos, x86_64-apple-macos, at: /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2024-09-11-a.xctoolchain/usr/lib/swift/embedded/Darwin.swiftmodule
10 | //===----------------------------------------------------------------------===//
11 | 
12 | #if canImport(Darwin)
  |               `- error: could not find module 'Darwin' for target 'riscv32-none-none-eabi'; found: arm64-apple-macos, arm64e-apple-macos, x86_64-apple-macos, at: /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2024-09-11-a.xctoolchain/usr/lib/swift/embedded/Darwin.swiftmodule
13 | import Darwin
14 | #endif

[colemancda]

@erhankur That's odd, I did not get that error with toolchain swift-DEVELOPMENT-SNAPSHOT-2024-10-30-a, I will download the latest and try again.