Call mixerSuspend and mixerResume when moving to/from background on iOS

[raggy]

Addresses #401

[CedNaru]

Is there a reason why it's for iOS only and not enable for Android ?
That notification only exist for those 2 platforms, Android is likely to have the same issue.

[Copilot]

Pull Request Overview

This PR adds support for calling FMOD's mixerSuspend and mixerResume functions when an iOS application moves to/from the background, addressing issue #401.

• Exposes two new methods mixer_suspend() and mixer_resume() in the FmodServer C++ API
• Integrates these methods into the GDScript bindings for use in Godot
• Implements automatic suspension/resumption in the demo FmodManager when the iOS app loses/gains focus

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/fmod_server.h	Adds public method declarations for mixer_suspend() and mixer_resume()
src/fmod_server.cpp	Implements the new methods as wrappers around FMOD's core system mixer functions and registers them with Godot's class binding system
demo/addons/fmod/FmodManager.gd	Calls the new mixer methods in response to iOS application focus notifications to properly suspend/resume audio when backgrounded

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[Copilot]

According to FMOD documentation, mixerSuspend() and mixerResume() should be called when the app goes to the background on mobile platforms, not just iOS. Consider also handling Android by checking for OS.has_feature("android") in addition to iOS. This would ensure proper audio handling when the app is backgrounded on all mobile platforms.

Suggested change

	if OS.has_feature("ios"):
	if OS.has_feature("ios") or OS.has_feature("android"):

[raggy]

Is there a reason why it's for iOS only and not enable for Android ? That notification only exist for those 2 platforms, Android is likely to have the same issue.

We weren't finding any issues with Android sound not returning, but I agree that this solution would be totally fine for Android too. On Android I believe the sound just continues in the background unless you choose to mute it.