Updates product_storage (enabled, quantity). Requires authenticated account when quantity is sent. At least one of enabled or quantity must be provided.
storage_logs (inventory movements table):
| Request | storage_logs |
| { “quantity”: N } (tracking on) | Yes — LOAD/UNLOAD row with quantity_before / quantity_after |
| { “enabled”: true, “quantity”: N } | Yes — after activation |
| { “enabled”: true } only | No — no quantity change |
| { “enabled”: false } | No — tracking off only |
| Same quantity as current | No — no movement |
Quantity updates are rejected when tracking is not enabled (unless enabled=true in the same request). Movements appear under GET /{id}/inventory-movements.