fix(mobile): fix unreachable back button on subscription screen

Missing safe-area top inset pushed the header (back arrow + title)
up under the status bar/notch, overlapping the clock and making the
button effectively untappable. Also falls back to router.replace
when there's no back history instead of silently no-op'ing.

apps/mobile/src/app/account/subscription.tsx

@@ -1,6 +1,7 @@
 import { useCallback, useEffect, useState } from "react";
 import { router } from "expo-router";
 import { ActivityIndicator, Alert, Pressable, ScrollView, Text, View } from "react-native";
+import { useSafeAreaInsets } from "react-native-safe-area-context";
 import { Ionicons } from "@expo/vector-icons";
 import type { CustomerInfo, PurchasesOffering, PurchasesPackage } from "react-native-purchases";
 import Purchases from "react-native-purchases";
@@ -8,6 +9,7 @@ import { getActiveRestaurant } from "@/lib/active-restaurant";
 import { configurePurchases, getCurrentOffering, getCustomerInfo, isProActive, PRO_ENTITLEMENT_ID } from "@/lib/purchases";
 
 export default function SubscriptionScreen() {
+  const insets = useSafeAreaInsets();
   const [loading, setLoading] = useState(true);
   const [offering, setOffering] = useState<PurchasesOffering | null>(null);
   const [customerInfo, setCustomerInfo] = useState<CustomerInfo | null>(null);
@@ -83,9 +85,16 @@ export default function SubscriptionScreen() {
   }
 
   return (
-    <ScrollView style={{ flex: 1, backgroundColor: "#FAF8F5" }} contentContainerStyle={{ padding: 20, gap: 16 }}>
+    <ScrollView
+      style={{ flex: 1, backgroundColor: "#FAF8F5" }}
+      contentContainerStyle={{ padding: 20, paddingTop: insets.top + 12, gap: 16 }}
+    >
       <View style={{ flexDirection: "row", alignItems: "center", gap: 8 }}>
-        <Pressable onPress={() => router.back()} style={{ padding: 4 }}>
+        <Pressable
+          onPress={() => (router.canGoBack() ? router.back() : router.replace("/account"))}
+          hitSlop={12}
+          style={{ padding: 8 }}
+        >
           <Ionicons name="arrow-back" size={22} color="#1C1917" />
         </Pressable>
         <Text style={{ fontSize: 22, fontWeight: "800", color: "#1C1917" }}>Abonelik</Text>