MAINT-2301 : Change messaging in the Merchant Outbox panel when an error happened, so not to be confused with the not-a-merchant case.

MAINT-2301 : Do not treat 404 errors (server returns not found) as 403 errors (forbidden, i.e. resident is not a merchant)

MAINT-2287 : Fixed : Test the merchant/no merchant status without relying on outbox, Recreate missing outbox for a merchant, UI clean up on init.

MAINT-2287 : WIP : Make inbox and outbox visible and accessible if InventoryOutboxMakeVisible is set (default is false)

Fix dangling references.