Refactor generic WinRT interfaces

[halildurmus]

Description

• IAsyncOperation, IIterator, IKeyValuePair, IMap, IMapView, IVector, and IVectorView classes are now abstract
• Adds private subclasses for the supported type arguments of the above classes (e.g. _IAsyncOperationBool class for IAsyncOperation<bool> types).
• Adds WinRTIntType enum (replaces Type parameters on the above classes)

With these changes, performance should be improved as type checks are only performed once in factory constructors instead of when each instance method is called, and also the code is cleaner now.

We should definitely explore whether we can automate the generation of these private subclasses in the future, as they are very time-consuming and error-prone to manage at the moment.

Related Issue

None

Type of Change

• ✨ New feature (non-breaking change which adds functionality)
• 🛠️ Bug fix (non-breaking change which fixes an issue)
• ❌ Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Code refactor
• ✅ Build configuration change
• 📝 Documentation
• 🗑️ Chore