Add support for multiple codes per cheat entry and misc tweaks
* Imagine: Update bundled libc++ to LLVM 19-rc2
* Imagine: Replace usage of contains() with std::ranges::contains()
* Imagine: Fix ZArray to satisfy range concept and add toIterator() utility function
* EmuFramework: Add a generic cheat API in EmuSystem to support setting multiple codes per cheat
* EmuFramework: Rewrite all cheat GUI views to share more common code
* EmuFramework: Add confirmation before deleting a cheat
* GBA.emu, GBC.emu, MD.emu, NES.emu, Snes9x: Remove cheat entry limits and update to new cheat API