refactor(test): standardize file naming and migrate from JWT to Basic Auth

[pinglin]

Because

• Integration test file naming was inconsistent with other repositories (used underscore _ instead of dash -)
• CE now only supports Basic Auth; JWT authentication is EE-only
• Proto files were outdated and needed to match current protobuf definitions

This commit

• Rename all integration test files from underscore to dash format for consistency:
  • grpc_create_model.js → grpc-create-model.js
  • rest_create_model.js → rest-create-model.js
  • etc.
• Rename JWT test files to Basic Auth:
  • rest_create_model_with_jwt.js → rest-create-model-with-basic-auth.js
  • rest_deploy_model_with_jwt.js → rest-deploy-model-with-basic-auth.js
  • rest_model_card_with_jwt.js → rest-model-card-with-basic-auth.js
  • rest_publish_model_with_jwt.js → rest-publish-model-with-basic-auth.js
  • rest_query_model_with_jwt.js → rest-query-model-with-basic-auth.js
  • rest_update_model_with_jwt.js → rest-update-model-with-basic-auth.js
  • rest_with_jwt.js → rest-with-basic-auth.js
• Add getBasicAuthHeader() helper function for Basic Auth encoding
• Update setup() functions in grpc.js and rest.js to use Basic Auth instead of JWT login
• Update gRPC client proto loading paths
• Update health check endpoint from /v1alpha/health/model to /v1beta/health/model
• Update proto files to match current protobuf definitions