Refine display of ticket photo label for a more polished interface

Removes the "(optionnel)" text from the ticket photo label in `NewSaleFormMulti.tsx` and updates `replit.md`.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 4b008663-bd72-492b-b0b6-fa252367e730
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/0715008c-7244-40f4-befc-26c014852236/4b008663-bd72-492b-b0b6-fa252367e730/Rb1L0tF

client/src/components/NewSaleFormMulti.tsx

@@ -691,7 +691,7 @@ export default function NewSaleFormMulti() {
 
               {/* Photo Ticket */}
               <div className="space-y-2">
-                <label className="text-sm font-medium">Photo du ticket (optionnel)</label>
+                <label className="text-sm font-medium">Photo du ticket</label>
                 <div className="flex gap-2 max-w-md">
                   <Button
                     type="button"