refactor: simplify upload rules and remove destination flow

lib/validate-folder.ts

@@ -2,17 +2,11 @@
 // Client-side folder validation
 // ---------------------------------------------------------------------------
 
-import { REQUIRED_TEXTURES, TEXTURE_EXTENSIONS } from '@/lib/constants'
+import { TEXTURE_EXTENSIONS } from '@/lib/constants'
 import type { TextureFile } from '@/lib/client-types'
 
 const TEXTURE_EXT_ARRAY = [...TEXTURE_EXTENSIONS]
 
-function getTextureType(filename: string): string | null {
-  const name = filename.toLowerCase().replace(/\.[^.]+$/, '')
-  if ((REQUIRED_TEXTURES as readonly string[]).includes(name)) return name
-  return null
-}
-
 /** Discriminated union: either valid (with model) or invalid (with errors). */
 export type ValidationResult =
   | { ok: true; model: File; textures: TextureFile[]; warnings: string[] }
@@ -20,39 +14,33 @@ export type ValidationResult =
 
 export function validateFolder(files: File[]): ValidationResult {
   const textures: TextureFile[] = []
-  const warnings: string[] = []
   const errors: string[] = []
 
   const modelFiles = files.filter((f) => {
     const name = f.name.toLowerCase()
-    return name === 'model.glb' || name === 'model.gltf'
+    return name === 'model.glb'
   })
 
   if (modelFiles.length === 0) {
-    return { ok: false, errors: ['model.glb ou model.gltf manquant (obligatoire)'] }
+    return { ok: false, errors: ['model.glb manquant (obligatoire)'] }
+  }
+
+  if (modelFiles.length > 1) {
+    return { ok: false, errors: ['Un seul fichier model.glb est autorise'] }
   }
 
   const textureFiles = files.filter((f) => {
     const ext = f.name.slice(f.name.lastIndexOf('.')).toLowerCase()
-    return TEXTURE_EXT_ARRAY.includes(ext) && getTextureType(f.name) !== null
+    return TEXTURE_EXT_ARRAY.includes(ext)
   })
 
   for (const tf of textureFiles) {
     textures.push({ name: tf.name, file: tf })
   }
 
-  const foundTextures = new Set(
-    textures.map((t) => t.name.toLowerCase().replace(/\.[^.]+$/, '')),
-  )
-  for (const req of REQUIRED_TEXTURES) {
-    if (!foundTextures.has(req)) {
-      warnings.push(`${req}.webp/png/jpg manquant`)
-    }
-  }
-
   if (errors.length > 0) {
     return { ok: false, errors }
   }
 
-  return { ok: true, model: modelFiles[0], textures, warnings }
+  return { ok: true, model: modelFiles[0], textures, warnings: [] }
 }