1.2.4 — Fabric — Data safety and advanced hopper fixes

This update improves storage data protection and fixes advanced hopper and batch export behavior.

• Storage now uses a single SavedData file with background snapshots. Existing digitalstorage/ data is migrated on upgrade, with the old directory retained as a backup.
• Unrecognized item data is preserved. Damaged or newer-version data is protected from being overwritten with empty data, and accessors keep their bindings when a volume is temporarily unavailable.
• The combined item-variant data budget defaults to 64 MiB across all accounts and volumes. Existing over-limit data remains readable and extractable; additions are rejected until usage is within the limit.
• Mounted volumes cannot be deleted. Servers may configure a limit above 64 volumes.
• Advanced hoppers can now feed a bound digital accessor directly. Newly placed hoppers use DSC's own block entity; existing hoppers remain compatible. Ordinary Tom's Storage hoppers keep their behavior.
• Fixed batch export to eligible Sophisticated Storage containers reporting insufficient space while usable slots remained. One export can now fill the available insertable slots.