[Linter Rule] Add warning if service spec has naming conflict within one client or with azure core models

[MaryGao]

Clear and concise description of the problem

Any rule to resolve the naming conflict will be wired and just workaround no matter we use AutoGenerated in m4 or any prefix we may use in language emitter.

I would suggest we add a warning for any naming conflicts if happening within clients or within referred azure core models see an example.

Checklist

• [X] Follow our Code of Conduct
• [X] Check that this issue is about the Azure libraries for typespec. For feature request in the typespec language or core libraries file it in the TypeSpec repo
• [X] Read the docs.
• [X] Check that there isn't already an issue that request the same feature to avoid creating a duplicate.