[BUG] Preview/proxy URL double-prepends base_path when using sub-path deployment

[toaruI]

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OpenList Version (required)

v4.1.10

Storage Driver Used (required)

115

Bug Description (required)

When deploying with site_url containing a sub-path (/115hide),
the frontend generates preview URLs with duplicated base_path:

Expected: /115hide/115/file.mp4
Actual: /115hide/115//115hide/115/file.mp4

API raw_url is correct (returns CDN direct link).
Issue is in frontend URL construction for proxy/preview requests.

Logs (required)

For example
GET /115hide/115/folder1//115hide/115/folder1/myvideo.mp4/myvideo.mp4 HTTP/2.0" 200 1497 "-" "Mozilla/5.0

in the website logs

Configuration File Content (required)

from 1panel
in a Docker

Reproduction Link (optional)

No response