Fix form error display for root-level validation errors

When validation errors occur at the root level (e.g., from :fn validators
in multi schemas), they are returned as a vector directly rather than a
map with :errors key. Update default-step-footer to handle both cases.

src/clj/auto_ap/ssr/components/multi_modal.clj

@@ -148,7 +148,9 @@
                                                         next-button-content]}]
   [:div.flex.justify-end
    [:div.flex.items-baseline.gap-x-4
-    (com/form-errors {:errors (:errors (:step-params fc/*form-errors*))})
+     (let [step-errors (:step-params fc/*form-errors*)]
+       (com/form-errors {:errors (or (:errors step-errors)
+                                     (when (sequential? step-errors) step-errors))}))
     (when (not= (first (steps linear-wizard))
                 (step-key step))
       (when validation-route