- Add a dependency group for net8.0 to the nuspec

Some target frameworks declared in the dependencies group of the nuspec and the lib/ref folder do not have exact matches in the other location. Consult the list of actions below:

A stable release of a package should not have a prerelease dependency. Either modify the version spec of dependency "Microsoft.SemanticKernel.Connectors.Google

A stable release of a package should not have a prerelease dependency. Either modify the version spec of dependency "ModelContextProtocol.AspNetCore

Dereference of a possibly null reference.

Possible null reference assignment.

'VoiceService' is obsolete: 'This is temporary, duct-tape like solution. It can and will evolve into something more robust'

'VoiceService' is obsolete: 'This is temporary, duct-tape like solution. It can and will evolve into something more robust'

'VoiceService' is obsolete: 'This is temporary, duct-tape like solution. It can and will evolve into something more robust'

Possible null reference argument for parameter 'text' in 'Task<string> IKernelMemory.ImportTextAsync(string text, string? documentId = null, TagCollection? tags = null, string? index = null, IEnumerable<string>? steps = null, IContext? context = null, CancellationToken cancellationToken = default(CancellationToken))'.

'VoiceService' is obsolete: 'This is temporary, duct-tape like solution. It can and will evolve into something more robust'

Possible null reference argument for parameter 'json' in 'JsonDocument JsonDocument.Parse(string json, JsonDocumentOptions options = default(JsonDocumentOptions))'.

Dereference of a possibly null reference.