Interface
Common
```kotlin
public interface CompositionServices
```
Allows finding composition services from the runtime. The services requested through this
interface are internal to the runtime and cannot be provided directly.
The `CompositionServices` interface is used by the runtime to provide optional and/or
experimental services through public extension functions.
Implementation of `Composition` that delegate to another `Composition` instance should implement
this interface and delegate calls to `getCompositionService` to the original `Composition`.
## Functions
getCompositionService
```kotlin
public fun getCompositionService(key: CompositionServiceKey): T?
```
Find a service of class `T`.