Remove 2>/dev/null from for-loop glob pattern which causes syntax
error in BusyBox ash shell. The [ -f "$zf" ] check handles the
case when no zone files exist.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Add comprehensive zone management for DNS master functionality:
- vortexctl zone list/dump/import/export/reload commands
- Secondary DNS provider configuration (OVH support)
- RPCD methods for LuCI integration
- ACL permissions for new methods
This enables importing zones from external providers (Gandi) and
configuring OVH as secondary DNS with SecuBox as authoritative master.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>