Added library export experimental feature

[polyxneg]

Mark the type contribution you are making:

• Experimental feature (new functionality that can be selectively enabled/disabled)
• Bug fix (non-breaking change which fixes an issue)

Description

Summary of your changes, including:

• Why is this change necessary?
  So gaming launchers like LudiHub which I developed can import the game shortcuts from Delta with the tap of a button
• Why did you decide on this solution?
  Because it was adopted by other emulators and it works flawlessly

Testing

List all iOS versions and devices you've tested this change on.

• iPhone 17 iOS 26.5.1
• iPad mini 7 iOS 27 Beta

Checklist

General (All PRs)

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I've tested my changes with different device + OS version configurations

Experimental Feature-specific

• Added property to ExperimentalFeatures struct annotated with @Feature
• Uses @Option's to persist all feature-related data
• Locked all behavior changes behind ExperimentalFeatures.shared.[feature].isEnabled runtime check
• Isolates changes to separate files as much as possible (e.g. via Swift extensions)

[rileytestut]

Awesome everything looks good to me! Just have one question about whether you're intentionally not including box art for games that Delta provided box art for automatically (it's totally fine if you are), but otherwise happy to merge in 👍

[polyxneg]

Oh I didn’t notice it! I can add it as well unless you want to add it after merging it.

[polyxneg]

@rileytestut I expanded the LibraryExport class and added the cached images. I tested it again and now it exports those too.

[rileytestut]

Amazing, will merge this and include in next Delta beta. Thanks!