Community Feedback Requested: Should we have named clients default to the default client if no default is registered?

When using DI, if `IVRChatClientFactory.CreateClient()` is called, and no default IVRChat was registered, then it will return the first available named client.

This may lead to unexpected behavior or bugs when consuming the library (and unaware of what the actual problem is), but also may make life easier when clients are left unregistered.

I wanted to obtain community feedback before implementing a complete change.

The implementation of this behavior is located [here](https://github.com/binn/VRChat.API.Client/blob/3ee8416a5108553e0e4e9b05b9a2f1007052962d/VRChat.API.Extensions.Hosting/DefaultVRChatClientFactory.cs#L29) and [here](https://github.com/binn/VRChat.API.Client/blob/3ee8416a5108553e0e4e9b05b9a2f1007052962d/VRChat.API.Extensions.Hosting/VRChatServiceCollectionExtensions.cs#L87)

Start by reading DefaultVRChatClientFactory.cs and VRChatServiceCollectionExtensions.cs at the linked locations to understand how CreateClient() selects a named client when no default is registered. Review the issue's proposed alternatives and gather the requested community feedback; done means the expected behavior is decided and the implementation scope is documented.

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