[typespec-python] Bug in generating renamed models

[YalinLi0312]

Renamed models themselves are generated correctly, but not get propagated to all of the usages like in operations and models.
For example, in AppConfig, we renamed the model "Error" to "AppConfigError" in tsp. While in generated code, it's still using the old name as return type in some operations, like in begin_create_snapshot() (note: the return type of this method does not generate correctly, should be LRO[_models.Snapshot]) Also in models, like in model OperationDetails.

Expected:
Should generate with the new name on the renamed models in all usages in the package.

[msyyc]

@YalinLi0312

• OperationDetails.error refers to Foundations.Error instead of your renamed Error defined in https://github.com/Azure/azure-rest-api-specs/blob/ba268c5654f002bc17914e0bc157f19529f1fec1/specification/appconfiguration/AppConfiguration/models.tsp#L137 so it is not renamed. You could confirm with tsp author whether it is expected
• return type of begin_create_snapshot is wrong which causes by bug of typespec-azure-core and I have created issue [typespec-azure-core] getLroMetadata returns wrong final result typespec-azure#1407 to track it.
• python emitter doesn't generate Error which is bug of TCGC and I also create an issue to track [TCGC] tcgc shall not clear usage for models under namespace Azure.Core typespec-azure#1408

[msyyc]

@YalinLi0312 About return type of begin_create_snapshot is wrong which causes by bug of typespec-azure-core and I have created issue https://github.com/Azure/typespec-azure/issues/1407 to track it., according to Azure/typespec-azure#1407 (comment), the typespec author shall update the typespec definition.