Possible null reference return.

Dereference of a possibly null reference.

The type 'YouTubeSummariser.Services.Configurations.OpenAISettings?' cannot be used as type parameter 'TService' in the generic type or method 'ServiceCollectionServiceExtensions.AddSingleton<TService>(IServiceCollection, TService)'. Nullability of type argument 'YouTubeSummariser.Services.Configurations.OpenAISettings?' doesn't match 'class' constraint.

Dereference of a possibly null reference.

The type 'YouTubeSummariser.Services.Configurations.PromptSettings?' cannot be used as type parameter 'TService' in the generic type or method 'ServiceCollectionServiceExtensions.AddSingleton<TService>(IServiceCollection, TService)'. Nullability of type argument 'YouTubeSummariser.Services.Configurations.PromptSettings?' doesn't match 'class' constraint.

Dereference of a possibly null reference.

Possible null reference argument for parameter 'uriString' in 'Uri.Uri(string uriString)'.

Possible null reference argument for parameter 'key' in 'AzureKeyCredential.AzureKeyCredential(string key)'.

Prefer 'static readonly' fields over constant array arguments if the called method is called repeatedly and is not mutating the passed array (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1861)