feat(filebrowser-quantum): clone filebrowser

[SimJoSt]

App Addition

• I have opened an issue to discuss this app addition before submitting this pull request: [App Request]: FileBrowser Quantum #4015

Description

Adds FileBrowser Quantum to the community train.

FileBrowser Quantum provides an easy way to access and manage your files from the web. It has a modern responsive interface that has many advanced features to manage users, access, sharing, and file preview and editing.
Fork of File Browser.

App Information

• Upstream: https://github.com/gtsteffaniak/filebrowser
• Documentation: https://filebrowserquantum.com/en/docs/
• App Version: 1.1.0

Testing

Tested locally with:

• basic-values.yaml

All tests passed successfully.

Icons and Screenshots

Please upload the following to the CDN:

• Icon: https://github.com/user-attachments/assets/c40b22c9-33da-47b7-bc4c-ce69bb5cc174
• Screenshot 1: https://selfh.st/content/images/size/w960/format/webp/2025/12/2025-12-03-filebrowser-quantum-featured-image.png
• Screenshot 2: https://cdn.jsdelivr.net/gh/selfhst/cdn/assets/images/blog/2025/12/03/filebrowser-quantum-login-screen.webp
• Screenshot 3: https://cdn.jsdelivr.net/gh/selfhst/cdn/assets/images/blog/2025/12/03/filebrowser-quantum-customizable-sidebar.webp
• Screenshot 4: https://cdn.jsdelivr.net/gh/selfhst/cdn/assets/images/blog/2025/12/03/filebrowser-quantum-duplicate-finder.webp
• Screenshot 5: https://cdn.jsdelivr.net/gh/selfhst/cdn/assets/images/blog/2025/12/03/filebrowser-quantum-context-menu.webp
• Screenshot 6: https://cdn.jsdelivr.net/gh/selfhst/cdn/assets/images/blog/2025/12/03/filebrowser-quantum-gallery-view-mode.webp

(Source: https://selfh.st/post/filebrowser-quantum-hits-stable/)

Special Notes

• First-time setup instructions: [if applicable]
• Any other important information

Checklist

• App runs successfully locally
• Only modified files under /ix-dev/ or /library/
• README.md included
• Multiple test scenarios tested
• questions.yaml has clear descriptions and follows structure of existing apps
• All automated CI checks pass