feat(Lu): enhance Lu integration with improved game context support

[luf1k]

Update Lu integration with the following improvements:

• Add support for gameplay data attachments (screenshots and save states)
• Track attachment and save state capability per game
• Enhance API context with detailed game state information
• Improve logging for better troubleshooting
• Update legal information URL to https://www.lulabs.ai/legal

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

This PR enhances the Lu integration with more detailed gameplay information, enabling more personalized and helpful responses for users. The changes include:

• Why is this change necessary?

  • The existing Lu integration lacked context about the player's current gameplay state
  • Users would get generic responses without the ability to share screenshots or save states
  • The system couldn't determine if a game supported attachments/save states
  • Troubleshooting was difficult due to limited logging

• Why did you decide on this solution?

  • Adding capability tracking per game allows for intelligent feature availability
  • Including save state metadata provides Lu with player progress context
  • Adding attachments (screenshots/save states) enables deeper and real-time understanding of gameplay
  • Enhanced logging improves debugging and support capabilities
  • All features are properly gated behind experimental feature flags and user opt-in
  • Creating disposable save states to eliminate any impact on user-managed states and delete them after sending

Testing

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

Example Configurations:

• iPhone 12, iOS 18.1.1
• iPhone 15 Pro Max 18.3.1

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)