feat: speed up admin clone import and enable Cache Components

- Clone import: defer FurnitureData.json writes and append all entries in a
  single batched write instead of one read-modify-write per item, removing
  the main serialization bottleneck for large batches.
- Clone import: raise SSE batch concurrency cap from 5 to 10 and bump the
  clone client/route default from 2 to 6.
- Add a flush hook to runSseBatch so callers can batch deferred work before
  batch_complete is emitted, and surface flush errors as an error event.
- Enable Next.js Cache Components (instant: false opt-out) and silence the
  related build warnings in next.config.ts.
- Switch isomorphic-dompurify to dompurify and refresh dependencies.

src/app/api/admin/import/clone/batch/route.ts

@@ -7,6 +7,10 @@ import {
 	fetchSourceFurnidata,
 } from "@/lib/services/clone-import";
 import { getSource } from "@/lib/services/clone-sources";
+import {
+	appendFurniEntriesBatch,
+	appendFurniEntry,
+} from "@/lib/services/furni-data";
 import { runSseBatch } from "@/lib/services/import/core/sse-batch";
 
 interface BatchItem {
@@ -53,9 +57,17 @@ export const POST = withAdmin(
 		if (items.length > 500)
 			return apiError("Too many classnames (max 500)", 400);
 
+		// FurnitureData entries for successfully cloned items are appended once
+		// at the end (single read-modify-write instead of one per item), which
+		// removes the main serialization bottleneck when cloning hundreds of items.
+		const deferredEntries: Array<{
+			entry: Record<string, unknown>;
+			itemType: string;
+		}> = [];
+
 		return runSseBatch<BatchItem>({
 			items,
-			concurrency: body.concurrency || 2,
+			concurrency: body.concurrency || 6,
 			signal: request.signal,
 			labelOf: (it) => it.classname,
 			worker: async (it, _index, report) => {
@@ -71,9 +83,13 @@ export const POST = withAdmin(
 					source,
 					entry,
 					onProgress: report,
+					deferFurniData: true,
 				});
 
 				if (result.ok) {
+					if (result.furniDataEntry) {
+						deferredEntries.push(result.furniDataEntry);
+					}
 					logAudit({
 						userId: ctx.session.user.id,
 						action: "clone_furni",
@@ -93,6 +109,24 @@ export const POST = withAdmin(
 					error: result.error,
 				};
 			},
+			flush: async () => {
+				if (deferredEntries.length === 0) return;
+				try {
+					await appendFurniEntriesBatch(deferredEntries);
+				} catch (err) {
+					// Fallback so partial data survives: write each entry individually.
+					for (const { entry, itemType } of deferredEntries) {
+						try {
+							await appendFurniEntry(entry, itemType);
+						} catch {
+							/* best effort */
+						}
+					}
+					throw new Error(
+						`FurnitureData batch write failed: ${(err as Error).message}`,
+					);
+				}
+			},
 		});
 	},
 );

src/app/api/admin/import/clone/sync-all/route.ts

@@ -8,6 +8,10 @@ import {
 	fetchSourceFurnidata,
 } from "@/lib/services/clone-import";
 import { listSources } from "@/lib/services/clone-sources";
+import {
+	appendFurniEntriesBatch,
+	appendFurniEntry,
+} from "@/lib/services/furni-data";
 import { runSseBatch } from "@/lib/services/import/core/sse-batch";
 
 function sseEvent(data: unknown): string {
@@ -95,9 +99,16 @@ export const POST = withAdmin(
 			);
 		}
 
+		// FurnitureData entries are appended once at the end (single write) rather
+		// than once per item, removing the main serialization bottleneck.
+		const deferredEntries: Array<{
+			entry: Record<string, unknown>;
+			itemType: string;
+		}> = [];
+
 		return runSseBatch({
 			items: allItems,
-			concurrency: 2,
+			concurrency: 6,
 			signal: request.signal,
 			labelOf: (it) => `${it.sourceName}/${it.classname}`,
 			worker: async (it, _index, report) => {
@@ -129,9 +140,13 @@ export const POST = withAdmin(
 					source,
 					entry,
 					onProgress: report,
+					deferFurniData: true,
 				});
 
 				if (result.ok) {
+					if (result.furniDataEntry) {
+						deferredEntries.push(result.furniDataEntry);
+					}
 					logAudit({
 						userId: ctx.session.user.id,
 						action: "auto_sync_furni",
@@ -151,6 +166,23 @@ export const POST = withAdmin(
 					error: result.error,
 				};
 			},
+			flush: async () => {
+				if (deferredEntries.length === 0) return;
+				try {
+					await appendFurniEntriesBatch(deferredEntries);
+				} catch (err) {
+					for (const { entry, itemType } of deferredEntries) {
+						try {
+							await appendFurniEntry(entry, itemType);
+						} catch {
+							/* best effort */
+						}
+					}
+					throw new Error(
+						`FurnitureData batch write failed: ${(err as Error).message}`,
+					);
+				}
+			},
 		});
 	},
 );