refactor: simplify upload rules and remove destination flow

app/api/upload/check/route.ts

@@ -17,23 +17,21 @@ export async function POST(req: NextRequest) {
   if (authError) return authError
 
   let folderName: string
-  let destination: string
   let parsedFiles: Awaited<ReturnType<typeof parseMultiUpload>>['files']
 
   try {
     const parsed = await parseMultiUpload(req)
     folderName = parsed.folderName
-    destination = parsed.destination
     parsedFiles = parsed.files
   } catch (err) {
     const message = err instanceof Error ? err.message : 'Erreur inconnue'
     return NextResponse.json({ success: false, error: message }, { status: 400 })
   }
 
-  const folderPath = `public/models/${destination}/${folderName}`
+  const folderPath = `public/models/${folderName}`
 
   try {
-    const { filesToPush } = await prepareGitAssets({ folderName, destination, parsedFiles })
+    const { filesToPush } = await prepareGitAssets({ folderName, parsedFiles })
     const { exists, files } = await getRemoteFolder(folderPath)
 
     if (exists) {