refactor: simplify upload rules and remove destination flow

lib/parse-upload.ts

@@ -1,12 +1,11 @@
 import { extname } from 'path'
 import { NextRequest } from 'next/server'
 import { sanitizeFilename } from './sanitize'
-import { ALL_ALLOWED_EXTENSIONS, MODEL_EXTENSIONS, VALID_DESTINATIONS, MAX_FILE_SIZE } from './constants'
+import { ALL_ALLOWED_EXTENSIONS, MODEL_EXTENSIONS, MAX_FILE_SIZE } from './constants'
 import type { ParsedFile } from './types'
 
 export interface ParsedUpload {
   folderName: string
-  destination: string
   files: ParsedFile[]
   /** Any extra string fields from the FormData (e.g. "action") */
   extra: Record<string, string>
@@ -14,8 +13,8 @@ export interface ParsedUpload {
 
 /**
  * Parse a multi-file FormData upload request.
- * Validates destination, file extensions, file sizes, and returns parsed files.
- * Extra string fields (beyond folderName, destination, files, fileTypes, textureNames)
+ * Validates file extensions, file sizes, and returns parsed files.
+ * Extra string fields (beyond folderName, files, fileTypes, textureNames)
  * are returned in `extra`.
  */
 export async function parseMultiUpload(req: NextRequest): Promise<ParsedUpload> {
@@ -23,18 +22,12 @@ export async function parseMultiUpload(req: NextRequest): Promise<ParsedUpload>
   const folderName = (formData.get('folderName') as string | null)?.trim() || 'assets'
   const safeFolderName = sanitizeFilename(folderName).replace(/[^a-zA-Z0-9-_]/g, '-')
 
-  const rawDestination = (formData.get('destination') as string | null)?.trim() || 'general'
-  if (!VALID_DESTINATIONS.has(rawDestination)) {
-    throw new Error(`Destination invalide: "${rawDestination}"`)
-  }
-  const destination = rawDestination
-
   const rawFiles = formData.getAll('files')
   const fileTypes = formData.getAll('fileTypes') as string[]
   const textureNames = formData.getAll('textureNames') as string[]
 
   // Collect extra string fields
-  const knownKeys = new Set(['folderName', 'destination', 'files', 'fileTypes', 'textureNames'])
+  const knownKeys = new Set(['folderName', 'files', 'fileTypes', 'textureNames'])
   const extra: Record<string, string> = {}
   for (const [key, value] of formData.entries()) {
     if (!knownKeys.has(key) && typeof value === 'string') {
@@ -91,5 +84,5 @@ export async function parseMultiUpload(req: NextRequest): Promise<ParsedUpload>
     parsed.push({ filename, buffer, isModel })
   }
 
-  return { folderName: safeFolderName, destination, files: parsed, extra }
+  return { folderName: safeFolderName, files: parsed, extra }
 }