[TCGC][Bug] getAllModels, description is not correctly returned for scalar types

[haolingdong-msft]

TSP definition:

// namespace MyService.LongRunning
model JobResult
  is LroOperationStatus<{
    data: string;
  }>;

model LroOperationStatus<TStatusResult = never, TStatusError = Foundations.Error> {
  @key("operationId")
  @visibility("read")
  id: Azure.Core.uuid;

  @visibility("read")
  @lroStatus
  status: JobStatus;

  @visibility("read")
  createdDateTime?: utcDateTime;

  @visibility("read")
  expirationDateTime?: utcDateTime;

  @visibility("read")
  lastUpdateDateTime?: utcDateTime;

  error?: TStatusError;
  result?: TStatusResult;
}

// namespace Azure.Core;
/**
 * Universally Unique Identifier
 *
 * @example
 *
 * ```
 * 123e4567-e89b-12d3-a456-426614174000
 * ```
 */
@format("uuid")
scalar uuid extends string;

Neither the TCGC returned id property, nor the property.type have description Universally Unique Identifier. I think we should add the correct description on the type.
Other scalar types like boolean also have this issue.