Linux setquota/repquota require quota support on the underlying
filesystem. The target deployment is a Proxmox LXC on ZFS storage where
this is not available inside the container.
Removed: /api/quota endpoint, _quota_supported, _quota_usage,
_find_quota_fs, quotas.js, quota modal, dashboard quota table,
Quota button from share rows.
PLANNING.md updated: notes quota as out of scope with reason.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
