feat: add governed Team Folder subfolders and recovery

[cavazquez]

Summary

• add optional quotas for direct Team Folder subfolders; their actual usage also counts towards the parent Team Folder quota
• allow Team Folder administrators to assign scoped managers for direct subfolders from the Files sidebar
• retain delegated-manager assignments when advanced permissions are disabled, while suspending their effect until advanced permissions are enabled again
• add a recoverable Team Folder deletion flow with global-admin restore and permanent-purge actions
• permanently expire archived Team Folders after 30 days through a background job
• keep Team spaces protected from direct deletion and exclude archived folders from their active-folder queries
• expose the API surface in the OpenAPI specification and generated TypeScript types

Safety notes

• subfolder quota caps are not reserved allocations: configured caps may add up to more than the parent quota, but stored data cannot exceed the parent quota
• normal deletion of a child folder in Files still uses the regular Nextcloud trash; the recovery bin applies to deletion of the Team Folder itself

Compatibility

This PR targets master (currently Nextcloud 36). The working compatibility port for Nextcloud 34 is tracked separately in #5058.

Validation

• manual validation on the Nextcloud 34 compatibility port in Docker: direct subfolder quotas, quota enforcement, Team Folder archive, and restore
• ESLint, Stylelint, and production frontend build on the compatibility port
• regenerated OpenAPI specification and TypeScript types
• git diff --check after porting to master
• automated checks are pending on this PR

[artonge]

Couldn't this already be acheived by nesting Team Folders?

[artonge]

Also, to ease the review, of the subfolders and recovery do not depend on each other, please split this in two different PRs.

[artonge]

For awarness, this has really little chances to be backported :)

[artonge]

And do not forget to read our contribution guidelines, especially around AI usage: https://github.com/nextcloud/server/blob/master/.github/CONTRIBUTING.md