Create shared helper module for tsp-client commands

[samvaity]

Created shared helpers for tsp-client commands (common utility class used by multiple tools) so they provide single implementation of core logic

• Looser coupling (for multiple tool calls to use)
• Clear separation of “UI” (CLI command) vs logic

Will add update workflow in a follow-up PR, which will include details with the TspClientUpdate Tooling (it was increasing the size of PR)

[Copilot]

Pull Request Overview

This PR creates a shared helper module for tsp-client commands to improve code reusability and separation of concerns between CLI commands and business logic.

• Extracts common tsp-client convert logic into TspClientHelper with dependency injection
• Refactors TypeSpecConvertTool to use the new helper instead of duplicating convert logic
• Updates service registration and test files to accommodate the new dependency

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
TspConvertTool.cs	Removes duplicate convert logic and delegates to the new TspClientHelper
ServiceRegistrations.cs	Registers the new ITspClientHelper service for dependency injection
TspClientHelper.cs	New helper class implementing the shared tsp-client convert functionality
ITspClientHelper.cs	Interface defining the contract for tsp-client operations
TspConvertToolTest.cs	Updates test constructor calls to include the new dependency