perf(backend): cache avatar and banner url to db

packages/backend/src/core/entities/NoteEntityService.ts

@@ -415,7 +415,7 @@ export class NoteEntityService implements OnModuleInit {
 		await this.customEmojiService.prefetchEmojis(this.aggregateNoteEmojis(notes));
 		// TODO: 本当は renote とか reply がないのに renoteId とか replyId があったらここで解決しておく
 		const fileIds = notes.map(n => [n.fileIds, n.renote?.fileIds, n.reply?.fileIds]).flat(2).filter(isNotNull);
-		const packedFiles = await this.driveFileEntityService.packManyByIdsMap(fileIds);
+		const packedFiles = fileIds.length > 0 ? await this.driveFileEntityService.packManyByIdsMap(fileIds) : new Map();
 
 		return await Promise.all(notes.map(n => this.pack(n, me, {
 			...options,