[AC-2860] Revise unassigned and purchased seat warning for CB (#10077)

* Rework create-client-dialog seat warning

* Rework manage-client-subscription-dialog seat warning

* Fix create client purchased seats label

* Fix manage client subscription purchased seats label logic

* Another manage subscription purchased seats fix

apps/web/src/locales/en/messages.json

@@ -8564,5 +8564,8 @@
         "example": "Organization name"
       }
     }
+  },
+  "purchasedSeatsRemoved": {
+    "message": "purchased seats removed"
   }
 }