[MGMT] migrate resources lib to TypeSpec

[weidongxu-microsoft]

This is a hybrid of Swagger and TypeSpec

TypeSpec

• ResourceManagementClient
• private final SubscriptionClient subscriptionClient;
• private final PolicyClient policyClient;
• private final DeploymentStacksManagementClient deploymentStackClient;
• private final DataBoundariesManagementClient dataBoundaryClient;
• private final DeploymentsManagementClient deploymentClient;

Swagger

• private final FeatureClient featureClient;
• private final ManagementLockClient managementLockClient;
• private final ChangesManagementClient resourceChangeClient;

Plan is that a regen of e.g. resource would only delete the TypeSpec generated code from resources, then generate new code.
This would keep other code (Swgger, or e.g. policy) unchanged.

There could be some duplicated model that need special care.