Fix Multi-page demo in Dev Mode (#11955)
* Update init_helpers.ts
* Update init_helpers.ts
* Update init_helpers.ts to fix theme.css loading
* add changeset
* fix
* Fix endpoint bug
* Fix ts
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Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Freddy Boulton <41651716+freddyaboulton@users.noreply.github.com>
