fix(caldav): disable remote access when calendar federation is off

[st3iny]

• Resolves: none

Summary

As discussed in a meeting. Currently, only the creation of new federated shares is disabled. However, disabling the feature should also prevent remote instances from accessing the local calendar data.

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)

[st3iny]

/backport to stable32

[github-actions]

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