fix contrib system

src/pages/api/contribute/tool.ts

@@ -37,7 +37,7 @@ const ContributionRequestSchema = z.object({
   }),
   tool: ContributionToolSchema,
   metadata: z.object({
-    reason: z.string().max(500, 'Reason too long').optional()
+    reason: z.string().transform(val => val.trim() === '' ? undefined : val).optional()
   }).optional().default({})
 });