Fas 1b punkt 6: First Scan Coach + aktiveringsmätning

apps/mobile/src/app/(tabs)/scan.tsx

@@ -1,4 +1,4 @@
-import { useState } from "react";
+import { useEffect, useState } from "react";
 import { Alert, View } from "react-native";
 import { router } from "expo-router";
 import * as ImagePicker from "expo-image-picker";
@@ -17,6 +17,7 @@ import {
   Title,
 } from "@/components/ui";
 import { spacing } from "@/lib/theme";
+import { FirstScanCoach, useFirstScanCoach } from "@/components/FirstScanCoach";
 
 /** Skanna (spec §4.2): kyl, frys, skafferi, ingredienser, tallrik, kvitto, streckkod, datum, näringsdeklaration. */
 
@@ -43,11 +44,16 @@ interface Entitlements {
 
 export default function ScanScreen() {
   const [busyType, setBusyType] = useState<string | null>(null);
+  const coach = useFirstScanCoach();
   const entitlements = useQuery({
     queryKey: ["entitlements"],
     queryFn: () => api<Entitlements>("/v1/me/entitlements"),
   });
 
+  useEffect(() => {
+    void coach.showIfNeeded();
+  }, []);
+
   const startScan = async (scanType: string) => {
     if (scanType === "barcode") {
       router.push("/barcode");
@@ -93,6 +99,7 @@ export default function ScanScreen() {
 
   return (
     <Screen>
+      <FirstScanCoach visible={coach.visible} onDismiss={coach.dismiss} />
       <Title>{t("scan.title")}</Title>
       <Small>{t("scan.subtitle")}</Small>
       {quota != null && <Small>{t("scan.quotaLeft", { count: Math.max(0, quota) })}</Small>}