fix: graphe calculation

frontend/src/pages/CausalLab.tsx

@@ -34,6 +34,7 @@ interface InputMapping {
   field?: string
   unit?: string
   range?: number[]
+  normalize?: boolean
 }
 interface DataSources {
   prices:       { key: string; label: string }[]
@@ -1598,6 +1599,15 @@ function TabEditor({ initialId }: { initialId?: number | null }) {
                   </select>
                 </div>
               </>)}
+              {/* Normalisation /100 — visible uniquement pour sources surprise */}
+              {mapping.source === 'surprise' && (
+                <label className="flex items-center gap-2 cursor-pointer mt-1">
+                  <input type="checkbox" checked={!!mapping.normalize}
+                    onChange={e => updateMapping({ normalize: e.target.checked })}
+                    className="accent-cyan-500" />
+                  <span className="text-xs text-slate-400">Normaliser ÷100 <span className="text-slate-600">(coefs calibrés en fraction, pas en %)</span></span>
+                </label>
+              )}
             </div>
           )
         })()}