[tfjs-models/deeplab] why do we not have a save method in class SemanticSegmentation (to save the model in localstorage/indexdb)

[cu8code]

System Information

• TensorFlow.js version: 4.22.0
• Are you willing to contribute: Yes

Feature Request Description
I propose adding a save method to the SemanticSegmentation here class. Currently, I use a workaround where I save the model to IndexedDB after loading it. Here's my implementation:

let graphModel = null;
try {
    console.log("loading from memory");
    graphModel = await tfjs.loadGraphModel('indexeddb://deep');
    console.log("loaded from memory");
} catch (e) {
    console.log("failed to load from memory, loading from network");
    graphModel = await tfconv.loadGraphModel(
        modelConfig.modelUrl ||
        getURL(modelConfig.base!, modelConfig.quantizationBytes!)
    );
    console.log("saving to memory");
    graphModel.save("indexeddb://deep");
}

Impact on Current API
This addition would simplify workflows for browser-based applications.

Target Audience
Users running TensorFlow.js in the browser.