feat(files): Make Files app reusable

[tomek2k1]

There is a need to display files in other apps (e.g. Teams) in the same way as in the Files app, including all available features. This is the first step toward making the Files view available in other apps.

Assisted-by: Copilot:Claude-Sonnet-5

• Resolves: Display the team’s Files app embedded within the Teams app. circles#2663

Summary

TODO

• ...

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI

[marcoambrosini]

@tomek2k1, @artonge is available if you're stuck or need some guidance on this :)

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