280-ensure-ios-implementation-does-not-break-anything_4 Ready for PR

[Johnnyg63]

This pull request adds initial support for iOS as a build and runtime target. The main changes include platform detection for iOS, updates to OpenGL ES and image loader integration, and the introduction of a new C API header for iOS-specific functionality. The changes touch platform configuration, build system, OpenGL abstraction, and application API surfaces.

iOS Platform Support

• Added detection of iOS and iOS Simulator in config.h, defining OLC_HOST_IOS and related macros for proper platform differentiation.
• Updated the list of tested platforms in README.md to include iOS.

Build System Integration

• Updated Helpers.cmake to link iOS-specific frameworks (UIKit, Foundation, CoreGraphics, QuartzCore, Metal, MetalKit, OpenGLES, GLKit) when building examples for iOS.

OpenGL ES and Platform Abstraction

• Modified OpenGL abstraction in api_opengl.h and api_opengl.cpp to support iOS, including conditional compilation, header inclusion, and function pointer typedefs for OpenGL ES. [1] [2] [3] [4] [5] [6] [7] [8]
• Added iOS-specific diagnostic pragmas and friendly host naming for iOS builds. [1] [2] [3]

Image Loader and Core Integration

• Defined a new image loader type and class for iOS, and updated core.cpp to include the iOS image loader and host files. [1] [2] [3] [4]

iOS Application API

• Introduced a new header api_ios.h providing a C API for iOS-specific application, view controller, OpenGL ES renderer, image loader, and event handling (touch, keyboard, orientation, etc.). This enables integration with iOS runtime and Objective-C APIs.