Improve file handling in JS Client

[hannahblair]

Description

This PR adds a handle_file function, which converts a URL or File to FileData, or if it receives a Blob, it will just return the Blob as the client handles that anyway. This PR also fixes an issue with image uploading.

Methods of file handling that should work with this PR:

Passing a blob directly

const response = await fetch("https://raw.githubusercontent.com/gradio-app/gradio/main/test/test_files/bus.png");
const image_blob = await response_0.blob();
const result = client.submit("/lambda", { x: image_blob })

Passing a blob to handle_file

const response = await fetch("https://raw.githubusercontent.com/gradio-app/gradio/main/test/test_files/bus.png");
const image_blob = await response_0.blob();
const result = client.submit("/lambda", { x: handle_file(image_blob) })

Passing an image URL to handle_file

const image_url = "https://raw.githubusercontent.com/gradio-app/gradio/main/test/test_files/bus.png";
const result = client.submit("/lambda", { x: handle_file(image_url) })

Passing an image URL as an object

const image_url = "https://raw.githubusercontent.com/gradio-app/gradio/main/test/test_files/bus.png";
const result = client.submit("/lambda", { x: { path: image_url })

Passing a local file path to handle_file

const image_path = "./bus.png";
const result = client.submit("/lambda", { x: handle_file(image_path) )

Passing a Buffer to handle_file

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const imagePath = path.resolve(__dirname, "./bus.png");
const imageBuffer = fs.readFileSync(imagePath);

const result = client.submit("/lambda", { x: handle_file(imageBuffer) )

Passing an array of local image files to handle_file

const client = await Client.connect("hmb/image-simple-2"); // example space requiring two imgs
const result = await client.predict("/process_images", { image_list: [handle_file("./dog.png"), handle_file("./dog.png")] });

Closes: #6623 Closes: #8082 Closes: #7834 Closes: #8402 Clsoes: #8256

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Tests

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[gradio-pr-bot]

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---

Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/c4265462b96bbf2dc247f9dd2b55fcf190dc3037/gradio-4.33.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@c4265462b96bbf2dc247f9dd2b55fcf190dc3037#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-builds.s3.amazonaws.com/c4265462b96bbf2dc247f9dd2b55fcf190dc3037/gradio-client-0.20.1.tgz

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/client	patch
gradio	patch

• [ ] Maintainers can select this checkbox to manually select packages to update.

With the following changelog entry.

Improve file handling in JS Client

Maintainers or the PR author can modify the PR title to modify this entry.

#### Something isn't right?

- Maintainers can change the version label to modify the version bump. - If the bot has failed to detect any changes, or if this pull request needs to update multiple packages to different versions or requires a more comprehensive changelog entry, maintainers can [update the changelog file directly](https://github.com/gradio-app/gradio/edit/js-client-files/.changeset/violet-pans-doubt.md).

[pngwn]

Another case that should work is when the handle_file is passed as part of a nested object or array:

const image_url = "https://raw.githubusercontent.com/gradio-app/gradio/main/test/test_files/bus.png";
const result = client.submit("/lambda", { 
  x: {
    files: [handle_file(image_url), handle_file(image_url)]
  }
})