Missing property in Azure.AI.Agents.Persistent.SubmitToolApprovalUpdate

[stephentoub]

The type is exposing the Name and Arguments of the MCP tool call:
https://github.com/Azure/azure-sdk-for-net/blob/main/sdk/ai/Azure.AI.Agents.Persistent/src/Custom/Streaming/SubmitToolApprovalUpdate.cs
but it's not exposing the server label, such that the consumer doesn't know which server the tool call is from (there can be multiple servers that all have the same tool name).

The underlying RequiredMcpToolCall does expose this:

azure-sdk-for-net/sdk/ai/Azure.AI.Agents.Persistent/src/Generated/RequiredMcpToolCall.cs

Lines 54 to 58 in ea4b6a1

	public string Arguments { get; }
	/// <summary> The name of the function used on the MCP server. </summary>
	public string Name { get; }
	/// <summary> The label of the MCP server. </summary>
	public string ServerLabel { get; }

but that RequiredMcpToolCall instance is private to the SubmitToolApprovalUpdate and not accessible to a consumer.