Facebook iOS Bindings are outdated

### Description

Currently bound version: 16.3.1
Current version facebook offers: 18.0.0

In addition to several new features, the use of 16.3.1 is a blocker for many, because it lacks of privacy manifest files, which are required by Apple in order to publish new apps to the Apple App Store.

### Steps to Reproduce

Try to publish a new app to Apple App Store with 16.3.1 as dependency.

### Link to public reproduction project repository

_No response_

### Environment

- OS: macOS
- .NET MAUI: 9.0.301
- Target platforms: iOS

The issue names no files, tests, or entry points. Start by locating the Facebook iOS binding and its dependency version, then compare it with Facebook's 18.0.0 release and verify a .NET MAUI iOS app can meet App Store privacy-manifest requirements. Done means the binding is updated and the publication blocker is resolved.

索引モデルが issue の本文から書いたものです。