fix(translations): update French translation for 'donate' to remove emoji for consistency

feat(exercises-selection): replace hardcoded 'Add' text with translation key for localization support
style(workout-stepper-footer): enhance styling for footer buttons to improve visual consistency in light and dark modes

locales/fr.ts

@@ -386,7 +386,7 @@ export default {
     consent_banner: "Nous utilisons des cookies pour améliorer votre expérience. En cliquant sur Accepter, vous acceptez nos cookies.",
     about: "À propos",
     profile: "Profil",
-    donate: "Faire un don ❤️",
+    donate: "Faire un don",
     my_account: "Mon compte",
     dashboard: "Tableau de bord",
     home: "Accueil",

src/features/workout-builder/ui/exercises-selection.tsx

@@ -109,7 +109,7 @@ export const ExercisesSelection = ({
                     <div className="h-8 w-8 rounded-full bg-blue-600 flex items-center justify-center">
                       <Plus className="h-4 w-4 text-white" />
                     </div>
-                    <span className="font-medium">Add</span>
+                    <span className="font-medium">{t("commons.add")}</span>
                   </button>
                 </div>
               </div>

src/features/workout-builder/ui/workout-stepper-footer.tsx

@@ -35,9 +35,9 @@ export function WorkoutBuilderFooter({
         <div className="flex items-center justify-center"></div>
 
         {/* Navigation buttons */}
-        <div className="min-h-12 flex items-center justify-between gap-3 bg-white w-full p-0.5 border border-slate-400 dark:border-slate-700 rounded-full">
+        <div className="min-h-12 flex items-center justify-between gap-3 bg-white dark:bg-slate-900 w-full p-0.5 border border-slate-400 dark:border-slate-700 rounded-full">
           {/* Previous button */}
-          <Button className="flex-1 rounded-full" disabled={isFirstStep} onClick={onPrevious} size="default" variant="ghost">
+          <Button className="flex-1 rounded-full min-h-12" disabled={isFirstStep} onClick={onPrevious} size="default" variant="ghost">
             <div className="flex items-center gap-2">
               <ArrowLeft className="h-4 w-4" />
               <span className="font-medium">{t("workout_builder.navigation.previous")}</span>
@@ -46,7 +46,7 @@ export function WorkoutBuilderFooter({
 
           {/* Next/Start Workout button */}
           <Button
-            className="flex-1 rounded-full bg-blue-600 hover:bg-blue-700 min-h-12"
+            className="flex-1 rounded-full bg-blue-600 hover:bg-blue-700 min-h-12 dark:bg-blue-500 dark:hover:bg-blue-600"
             disabled={!canContinue}
             onClick={isFinalStep ? () => onStartWorkout?.() : onNext}
             size="default"