more fixes web + mobile

src/screens/Studio/ComposeSong.web.js

@@ -33,6 +33,8 @@ const MUSIC_GENERATION_COIN_COST = 8;
 const CONFIRM_MODAL_MAX_WIDTH = 540;
 const FUNCTIONS_REGION = "europe-west1";
 const VOICE_SECTION_TITLES = ["BASE", "SENSIBILITÉ", "TECHNIQUE"];
+const FIRST_VOICE_STEP_INDEX = 1;
+const OPTIONAL_VOICE_CATEGORIES = new Set(["SENSIBILITÉ", "TECHNIQUE"]);
 
 const ComposeSong = () => {
   const scrollRef = useRef(null);
@@ -115,9 +117,18 @@ const ComposeSong = () => {
     if (selectedIndex === 0) {
       return Array.isArray(genres) && genres.length > 0;
     }
-    if (selectedIndex === 1) {
-      return !!(voice && typeof voice === "object" && voice.BASE);
+
+    const voiceStepIndex = selectedIndex - FIRST_VOICE_STEP_INDEX;
+    const isVoiceStep =
+      voiceStepIndex >= 0 && voiceStepIndex < VOICE_SECTION_TITLES.length;
+    if (isVoiceStep) {
+      const category = VOICE_SECTION_TITLES[voiceStepIndex];
+      if (OPTIONAL_VOICE_CATEGORIES.has(category)) {
+        return true;
+      }
+      return !!(voice && typeof voice === "object" && voice[category]);
     }
+
     if (selectedIndex === instrumentStepIndex) {
       return Array.isArray(instruments) && instruments.length > 0;
     }