Ensure JS client status_callback functionality works and improve status messages

[hannahblair]

Description

This PR ensures the handle_space_success function is bound to the Client class, and that the logic is reached. I've also improved the messaging of the statuses so it doesn't show a generic error for a building or starting status.

To test:

await Client.connect("gradio/event_trigger", {
    status_callback: (space_status) =>
    console.log("Status updated: ", space_status)
});

Feel free to use or clone this sandbox to test (just download the tarfile for this PR and replace the .tgz and references to it in that sandbox).

Closes: #8695

🎯 PRs Should Target Issues

Before your create a PR, please check to see if there is an existing issue for this change. If not, please create an issue before you create this PR, unless the fix is very small.

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Tests

1. PRs will only be merged if tests pass on CI. To run the tests locally, please set up your Gradio environment locally and run the tests: bash scripts/run_all_tests.sh

2. You may need to run the linters: bash scripts/format_backend.sh and bash scripts/format_frontend.sh

[gradio-pr-bot]

🪼 branch checks and previews

•	Name	Status	URL
	Spaces	ready!	Spaces preview
	Website	ready!	Website preview
🦄	Changes	detected!	Details

---

Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/9155f4acf750b98d36aca5d1016e6ccb5e6e81c1/gradio-4.37.2-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@9155f4acf750b98d36aca5d1016e6ccb5e6e81c1#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-builds.s3.amazonaws.com/9155f4acf750b98d36aca5d1016e6ccb5e6e81c1/gradio-client-1.2.1.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.

Ensure JS client status_callback functionality works and improve status messages

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.

[pngwn]

Looks great. Thanks for fixing this @hannahblair!