feat(companies): onboard co-operative unions and farms

They hold a TIN but no business licence, so there is no eTrade record to look
their registration up in. A checkbox on the first wizard step marks them, and
everything that assumed a trade licence bends around it:

- The company step replaces the eTrade lookup with typed registration details
  — name, region, zone, woreda, kebele, house number — required exactly because
  they are now on screen. applyEtradeSourcedFields skips the lookup rather than
  failing it, so what the customer sends is what is stored.
- No freight-forwarder role. Forwarding is licensed work, so the option is not
  offered, and the API refuses it at start-onboarding and at every later
  role-add rather than letting approval fail on a document they cannot produce.
- No per-role business-licence upload, client-side or in the completion gate.
- Their own document set (company_onboarding_documents_cooperative) merges on
  top of the nationality one, admin-managed like every other set. Nationality
  wins a fileKey collision so no slot renders twice, and the DARS paper is not
  injected into it — the set it merges onto already carries one.
- The owner is typed in full; with no eTrade manager on file the licence
  comparison reports "nothing to compare against", which backoffice now
  explains rather than leaving as a bare dash.

Stored as an attributes flag, not a column: everything it changes is
behavioural, and nothing queries or joins on it.

apps/edr-freight-web/backoffice/src/components/layout/sidebar-sections.tsx

@@ -485,6 +485,18 @@ export const buildSidebarSections = (demoItems: SidebarItem[]): SidebarSection[]
         icon: <Settings />,
         permission: FREIGHT_PERMS.settings.dropdown.view,
       },
+      {
+        label: "Stamp settings",
+        href: "/dashboard/stamp-settings",
+        icon: <FileSignature />,
+        permission: FREIGHT_PERMS.settings.stamp.view,
+      },
+      {
+        label: "Invoice stamp",
+        href: "/dashboard/invoice-stamp-settings",
+        icon: <Receipt />,
+        permission: FREIGHT_PERMS.settings.invoiceStamp.view,
+      },
       {
         label: "Contract templates",
         href: "/dashboard/contract-templates",