feat(studio): add organize-imports tool with suggestion review and approval

Adds a Studio 'Organize imports' dialog that groups recently imported
furniture and furniture already sitting in the auto-created import
pages into suggested catalog categories.  Each group is presented with
its suggested name, icon, and layout which can be overridden before
approval; approved groups are turned into real catalog pages in a
single atomic export run.  Offers already inside the import subtree are
moved to the new pages; brand-new furniture gets a fresh offer.

- groupSuggestedCategories: generic pure helper reusing the same
  per-item label heuristic that drives suggestCategoryName; items with
  no label land in a 'Other Furni' remainder bucket
- GET /api/admin/import/organize: returns items from the imported
  furniture tree (catalog_items JOIN items_base via page id set from
  the imported-furniture root) union audit-logged but not-yet-placed
  recent imports; marks alreadyPlaced vs new
- organizeImportFurni server action: validates import-page membership
  before moving any offer, creates pages + inserts/moves items in one
  withCatalogExport snapshot, logs activity
- OrganizeImportsDialog: full-featured Studio dialog with price panel
  (applies to new offers only), parent select, per-group approval,
  editable name/icon/layout with suggestion reset chips, source tags
- import-pages.ts server helper: locates the imported-furniture tree
- Studio nav: 'Organize imports' button with FolderTree icon,
  gated on CATALOG_EDIT, wired next to the catalog manager
- en + nl translations for organizeImports.* keys with ICU plurals
- groupSuggestedCategories unit tests (deterministic grouping,
  remainder handling, size+alpha ordering, label consistency)

src/app/admin/studio/studio-layout-client.tsx

@@ -7,6 +7,7 @@ import {
 	ClipboardCheck,
 	Copy,
 	Dumbbell,
+	FolderTree,
 	Image as ImageIcon,
 	type LucideIcon,
 	Puzzle,
@@ -18,6 +19,7 @@ import {
 import { usePathname } from "next/navigation";
 import { useState } from "react";
 import { CatalogManagerDialog } from "@/app/admin/catalog/catalog-manager-dialog-wrapper";
+import { OrganizeImportsDialog } from "@/components/admin/studio/organize-imports-dialog";
 import Link from "@/components/link";
 import {
 	Popover,
@@ -113,6 +115,7 @@ export function StudioLayoutClient({
 	children: React.ReactNode;
 }) {
 	const pathname = usePathname() ?? "";
+	const [organizeOpen, setOrganizeOpen] = useState(false);
 	return (
 		<div className="flex h-[calc(100dvh-7rem)] min-h-[600px] min-w-0 flex-col overflow-hidden rounded-xl border border-[var(--admin-border)] bg-[var(--admin-canvas)] text-[var(--admin-text)]">
 			<nav
@@ -144,11 +147,21 @@ export function StudioLayoutClient({
 				</div>
 				<div className="flex flex-wrap gap-1">
 					{canEditCatalog && (
-						<CatalogManagerDialog
-							catalogType="normal"
-							canEdit
-							triggerLabel="Catalog manager"
-						/>
+						<>
+							<CatalogManagerDialog
+								catalogType="normal"
+								canEdit
+								triggerLabel="Catalog manager"
+							/>
+							<button
+								type="button"
+								onClick={() => setOrganizeOpen(true)}
+								className="flex min-h-10 items-center gap-2 rounded-lg px-3 text-sm font-medium text-[var(--admin-text-muted)] hover:bg-[var(--admin-accent)]/10"
+							>
+								<FolderTree size={16} />
+								Organize imports
+							</button>
+						</>
 					)}
 					<StudioMenu
 						label="Import & sync"
@@ -163,6 +176,12 @@ export function StudioLayoutClient({
 				</div>
 			</nav>
 			<div className="min-h-0 min-w-0 flex-1 overflow-auto">{children}</div>
+			{canEditCatalog && (
+				<OrganizeImportsDialog
+					open={organizeOpen}
+					onOpenChange={setOrganizeOpen}
+				/>
+			)}
 		</div>
 	);
 }