Documentation Improvement: Add Example Usage for Feature Flags

## Suggestion

It would be helpful to add a section in the documentation that provides example usage of how to implement feature flags using the Flagsmith iOS SDK. This would assist new users in understanding how to integrate the SDK effectively in their iOS applications.

### Proposed Content
- A step-by-step tutorial on initializing the SDK and configuring feature flags.
- Code snippets that demonstrate how to check for the status of a feature flag and enable/disable features in the app based on the flag status.
- Common use cases or scenarios where feature flags improve application deployment processes.

Including this information could enhance the onboarding process for new developers and increase the overall usability of the SDK.

Start by locating the iOS SDK documentation and the APIs for initializing the SDK and checking feature-flag status. Add a step-by-step integration tutorial with Swift snippets and common deployment use cases, then verify that the examples clearly show how flags control app features.

Written by the indexing model from the issue text.