Organize imports: drag & drop, virtualization, dupes, undo, days select, localStorage

- Native HTML5 drag & drop between categories with drop-target highlight
- Virtualized item lists via @tanstack/react-virtual (fixed 34px rows)
- Auto-batching of large groups (500 items / 50 groups per run)
- Duplicate detection against the destination page with badge + summary
- Per-category layout preview grid
- Undo history for item moves (single + batch, tracks source groups)
- Days-range selector to load older imports (30/60/90/180)
- LocalStorage persistence of user settings (mode, destination, price, days)
- Added translation keys across all 25 locales

src/messages/nl.json

@@ -2143,7 +2143,17 @@
 						"moveItemTo": "Verplaatsen naar…",
 						"batchMoveTo": "Geselecteerde verplaatsen naar…",
 						"selectedCount": "{count} geselecteerd",
-						"clearSelection": "Selectie wissen"
+						"clearSelection": "Selectie wissen",
+						"undo": "Ongedaan maken",
+						"daysLabel": "Dagen",
+						"daysValue": "{days} dagen",
+						"dupeSummary": "Al aanwezig op de bestemmingspagina: {count} item{count, plural, one {} other {s}}",
+						"layoutPreview": "Layoutvoorbeeld",
+						"emptyCategory": "Geen items in deze categorie",
+						"dupeOnDest": "Staat al op de bestemmingspagina",
+						"dupeOnDestShort": "duplicaat",
+						"errorPartial": "{failed} van de {total} rondes mislukt. Controleer en probeer opnieuw.",
+						"successCreateRuns": "{count, plural, one {1 pagina} other {# pagina's}} aangemaakt in {runs, plural, one {1 ronde} other {# rondes}} met {moved} verplaatst en {added} nieuw meubilair"
 					}
 				},
 				"bulk": {