fix(ui): i18n device-locale + share-pill rounded-full + Profile debug-marker

stores/language.ts:
- init() override AsyncStorage-Wert nicht — wenn nichts gespeichert,
  i18n bleibt bei deviceLocale (von lib/i18n.ts via Localization.getLocales).
  Vorher: forced 'en' default obwohl App auf DE.

ComposeCard share-button:
- borderRadius:12 + height:50 → rounded-full px-5 h-11 (44pt)
- text-base → text-sm. Pill-Pattern wie Pre-Session.

app/profile/index.tsx:
- AppHeader title "Profil" → "Profil DEBUG-2300" — TEMPORARY marker
  zur Verifikation ob File geladen wird (user-suspect: routing zu altem
  File). Wird nach Test wieder entfernt.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/rebreak-native/app/profile/index.tsx

@@ -156,7 +156,7 @@ export default function ProfileScreen() {
 
   return (
     <View style={{ flex: 1, backgroundColor: '#ffffff' }}>
-      <AppHeader showBack title="Profil" />
+      <AppHeader showBack title="Profil DEBUG-2300" />
       <ScrollView
         ref={scrollViewRef}
         style={{ flex: 1 }}

apps/rebreak-native/components/ComposeCard.tsx

@@ -163,18 +163,15 @@ export function ComposeCard({ onPosted }: Props) {
             <Pressable
               onPressIn={() => { if (!content.trim() || posting) return; submit(); }}
               disabled={!content.trim() || posting}
-              className="bg-rebreak-500 items-center justify-center"
+              className="bg-rebreak-500 items-center justify-center rounded-full px-5 h-11"
               style={({ pressed }) => ({
-                height: 50,
-                paddingHorizontal: 24,
-                borderRadius: 12,
                 opacity: pressed || !content.trim() || posting ? 0.5 : 1,
               })}
             >
               {posting ? (
                 <ActivityIndicator size="small" color="#fff" />
               ) : (
-                <Text className="text-white text-base" style={{ fontFamily: 'Nunito_600SemiBold' }}>{t('community.share')}</Text>
+                <Text className="text-white text-sm" style={{ fontFamily: 'Nunito_600SemiBold' }}>{t('community.share')}</Text>
               )}
             </Pressable>
           </View>

apps/rebreak-native/stores/language.ts

@@ -17,9 +17,14 @@ export const useLanguageStore = create<LanguageState>((set) => ({
 
   init: async () => {
     const stored = await AsyncStorage.getItem(STORAGE_KEY);
-    const lang: AppLanguage = stored === 'de' || stored === 'en' ? stored : 'en';
-    await i18n.changeLanguage(lang);
-    set({ language: lang });
+    if (stored === 'de' || stored === 'en') {
+      await i18n.changeLanguage(stored);
+      set({ language: stored });
+    } else {
+      // Kein expliziter Wert gespeichert — i18n.ts hat bereits via deviceLocale
+      // initialisiert (Localization.getLocales()). NICHT auf 'en' overriden.
+      set({ language: (i18n.language === 'de' ? 'de' : 'en') as AppLanguage });
+    }
   },
 
   setLanguage: async (lang) => {