Add csharp customizations for ServiceGroups migration

[meghanagupta95]

Add C#-scoped @@clientName decorators to client.tsp for the Azure.ResourceManager.ServiceGroups SDK migration from Swagger to TypeSpec.

Decorators added

Decorator	Purpose
@@clientName(ProvisioningState, "ServiceGroupProvisioningState", "csharp")	Match existing SDK naming
@@clientName(ServiceGroups, "ServiceGroupClient", "csharp")	Avoid C# namespace-type name conflict
@@clientName(ServiceGroupCollectionResponse, "ServiceGroupCollectionResult", "csharp")	AZC0030 compliance

Related SDK PR

Azure/azure-sdk-for-net#58532

[github-actions]

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[github-actions]

API Change Check

APIView identified API level changes in this PR and created the following API reviews

Language	API Review for Package
TypeSpec	Microsoft.Management
Go	sdk/resourcemanager/servicegroups/armservicegroups

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Comment generated by After APIView workflow run.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds C#-specific naming customizations in the TypeSpec client definition to support the Azure.ResourceManager.ServiceGroups migration and align generated C# naming with existing SDK conventions and analyzer rules.

Changes:

• Add @@clientName for ProvisioningState to match existing C# SDK naming.
• Add @@clientName for ServiceGroups to avoid a C# namespace/type name collision.
• Add @@clientName for ServiceGroupCollectionResponse to comply with AZC0030.