feat: introduce a function to bind a teamfolder to a team

[stediefan]

Assisted by: GitHub Copilot:Claude Sonnet 5
Assisted by: GitHub Copilot:GPT-5.6 Terra
Assisted by: GitHub Copilot:Kimi K2.7 Code

• Resolves: #
  Related Issues in Circles:
  Create team-folder when creating a team circles#2661
  Show team-folder contents on the TeamPage circles#2663
  Upgrade existing teams: create a path to turn a pre-existing team into a space (team+team-folder) through the same dialog and quota rules, reusing resources it already has instead of creating duplicates circles#2669

Related Pull Request in circles: nextcloud/circles#2675

Summary

This lays the foundation for the closer integration of circles (teams) and group/teamfolders
Both will depend on the Team- and FolderManager to create Teamfolders upon team creation and link those folders 1:1 to a team

TODO

• ...

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• [X ] Screenshots before/after for front-end changes
  not needed here
• 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

[CarlSchwan]

Look good

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