biorouter-headless doesn't accept valid public url prefixes

[minrk]

Describe the bug

biorouter-headless serve --public-url

doesn't accept valid URLs

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To Reproduce
Steps to reproduce the behavior:

1. biorouter-headless serve --public-url=http://example.org/url%40prefix/ or biorouter-headless serve --public-url=http://example.org/url@prefix/
2. See error:

Error: invalid path prefix "url%40prefix" derived from --public-url (allowed characters: letters, digits, and . _ ~ / -)

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Expected behavior
Valid URLs are supported

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Please provide the following information

• OS & Arch: [e.g. Ubuntu 22.04 x86] ubuntu 24.04
• Interface: [UI / CLI] CLI (headless)
• Version: [e.g. v1.0.2] 1.88.1
• Extensions enabled: N/A
• Provider & Model: N/A

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Additional context
This is for serving biorouter behind a JupyterHub proxy. In my case, an email address (including @) is in the URL prefix.