[DSIP-92][API] Should we introduce an official Dolphin Scheduler client?

### Search before asking

- [x] I had searched in the [DSIP](https://github.com/apache/dolphinscheduler/issues/14102) and found no similar DSIP.

### Motivation

If an official Dolphin Scheduler client is introduced, it would enable developers to interact with Dolphin Scheduler in new and flexible ways.

For example, an MCP server could be built on top of this client and integrated into LLM-based applications. A use case within the MCP client could be as simple as instructing the model to "create a workflow scheduler at 3:00 AM." MCP client would then invoke the MCP server, which in turn utilizes the Dolphin Scheduler client to automatically create the scheduled workflow.

Alternatively, the client could also be used in a traditional application — allowing developers to create workflows programmatically via API, without the need for a UI.

### Design Detail

No Design details at present, just an idea. May use swagger to generate a client automatically？

### Compatibility, Deprecation, and Migration Plan

No content.

### Test Plan

later.

### Code of Conduct

- [x] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

Start by reviewing the related DSIP issue 14102 and the proposal to use Swagger for client generation. The issue provides no implementation files, entry point, design, or test plan; the work is done only once the official client’s scope, design, compatibility plan, and tests are defined and implemented.

Written by the indexing model from the issue text.