feat(uat-batch-11): picker polish + BulkAddBerthsWizard currency + DocumentsHub root cleanup

- BulkAddBerthsWizard `priceCurrency` row + apply-to-all swapped from
  freetext Input to the shared CurrencySelect. Same idiom as
  berth-form + expense-form-dialog.
- /api/v1/yachts/autocomplete no longer short-circuits to `[]` when
  the search query is empty — the service returns the top 20
  most-recently-updated yachts so the picker has a useful default
  view the moment it opens. Saves the rep from a dead-end empty
  state.
- YachtPicker gains a fallback useQuery against `/api/v1/yachts/{id}`
  when the selected yacht isn't present in the current autocomplete
  window. Trigger label now shows the real name (was falling back to
  "Yacht <uuid-prefix>" when a parent pre-selected a value from a URL
  param).
- DocumentsHub: breadcrumb row only renders when a folder is
  selected. The "Home / All documents" placeholder was wasted
  vertical space above the PageHeader on the root view.

tsc clean. 1419/1419 vitest pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/yachts/yacht-picker.tsx

@@ -72,10 +72,23 @@ export function YachtPicker({
         )
       : rawOptions;
 
+  // When `value` is set but the selected yacht isn't in the current
+  // autocomplete window (e.g. parent pre-selected it from a URL param
+  // or the rep typed something that filtered it out), fetch its name
+  // by id so the trigger doesn't fall back to "Yacht <uuid-prefix>".
+  const fallbackQuery = useQuery<{ data: { name: string } }>({
+    queryKey: ['yacht-detail-label', value],
+    queryFn: () => apiFetch(`/api/v1/yachts/${value}`),
+    enabled: !!value && !rawOptions.some((o) => o.id === value),
+    staleTime: 60_000,
+  });
+
   const selectedLabel = (() => {
     if (!value) return placeholder;
     const match = rawOptions.find((o) => o.id === value);
-    return match?.name ?? `Yacht ${value.slice(0, 8)}`;
+    if (match) return match.name;
+    if (fallbackQuery.data?.data.name) return fallbackQuery.data.data.name;
+    return `Yacht ${value.slice(0, 8)}`;
   })();
 
   return (