Specify AttributeUsage on 'HangfireTelemetryFilter' to improve readability, even though it inherits it from its base type. (https://rules.sonarsource.com/csharp/RSPEC-3993)

Make this class name end with 'Attribute'. (https://rules.sonarsource.com/csharp/RSPEC-3376)

'S3StorageService' is an internal class that is apparently never instantiated. If so, remove the code from the assembly. If this class is intended to contain only static members, make it 'static' (Module in Visual Basic). (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1812)

In method 'BuildKey', replace the call to 'ToLowerInvariant' with 'ToUpperInvariant' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1308)

Modify 'RemoveAsync' to catch a more specific allowed exception type, or rethrow the exception (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1031)

In externally visible method 'IServiceCollection Extensions.AddHeroStorage(IServiceCollection services, IConfiguration configuration)', validate parameter 'configuration' is non-null before using it. If appropriate, throw an 'ArgumentNullException' when the argument is 'null'. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1062)

In method 'AddHeroStorage', replace the call to 'ToLowerInvariant' with 'ToUpperInvariant' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1308)

Change the type of property 'S3StorageOptions.PublicBaseUrl' from 'string' to 'System.Uri' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1056)

Change 'List<byte>' in 'FileUploadRequest.Data' to use 'Collection<T>', 'ReadOnlyCollection<T>' or 'KeyedCollection<K,V>' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1002)