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/me/route.ts

@@ -10,8 +10,6 @@ import { auth } from "@/lib/auth";
 import { sessionUserId } from "@/lib/auth/session-user";
 import { db, User } from "@/lib/db";
 
-export const dynamic = "force-dynamic";
-
 export async function GET(_req: Request) {
 	const session = await auth();
 	const id = sessionUserId(session?.user?.id);

src/app/api/me/tokens/route.ts

@@ -16,8 +16,6 @@ import { personalTokenScope } from "@/lib/auth/personal-token-scope";
 import { sessionUserId } from "@/lib/auth/session-user";
 import { db, PersonalAccessTokens } from "@/lib/db";
 
-export const dynamic = "force-dynamic";
-
 async function currentUserId(): Promise<number | null> {
 	const session = await auth();
 	return sessionUserId(session?.user?.id);