feat(mobile): show OTA update id next to app version

Meine Tiere tab footer now shows 'Version X.X.X - OTA <short-id>' (or
'Build (kein OTA)' when running the embedded/non-OTA bundle) via
expo-updates' Updates.isEmbeddedLaunch/updateId. Directly answers the
support question 'did the update actually arrive on this device?' by
comparing the shown short id against the 'Android update ID' an
'eas update' publish prints - the exact ambiguity that cost a multi-day
debugging session earlier (see .claude/handoffs/2026-09-12-ota-update-
mystery-expo-dev-client-root-cause.md).

Code-reviewed before commit (per WORKFLOW.md step 6): fixed two of four
findings - wrapped the expo-updates reads in a try/catch (LegalSection
sits outside FooterErrorBoundary, so an unguarded throw here would have
taken down the whole footer) and moved the hardcoded 'OTA ' prefix into
i18n (pets.otaId). The web-shim-always-unknown finding is a documented
dead branch (this app ships no web build - eas update only ever runs
--platform android). No test coverage added - no RN test infrastructure
exists in mobile/ yet (pre-existing gap, tracked in WORKFLOW.md).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

mobile/app/(app)/(tabs)/pets.tsx

@@ -4,6 +4,7 @@ import { useRouter } from "expo-router";
 import { useTranslation } from "react-i18next";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import Constants from "expo-constants";
+import * as Updates from "expo-updates";
 import * as Sentry from "@sentry/react-native";
 import { useAuth } from "@clerk/expo";
 import { Check, Sun, Moon, SunMoon } from "lucide-react-native";
@@ -216,12 +217,41 @@ function PetSuggestionsSection() {
   );
 }
 
-/** Links to the fixed-language legal pages (see root CLAUDE.md: not localized, always German) plus the installed app version, for anyone who needs to reach them without going through the web app. */
+/**
+ * Reads expo-updates' launch info defensively — these are plain native-module-backed exports, not
+ * function calls, but a stripped/misconfigured build (e.g. a dev client without the module properly
+ * linked) throwing here would otherwise crash LegalSection's render, and LegalSection sits outside
+ * FooterErrorBoundary (that only wraps LogoutSection below it), so there's no fallback UI to catch it.
+ * Not meaningful on the web target (the web shim always reports isEmbeddedLaunch=false/updateId=null) —
+ * this app has no shipped web build (`eas update` only ever runs `--platform android`, see README), so
+ * that's a dead branch today, not a live bug.
+ */
+function readOtaUpdateId(): { isEmbeddedLaunch: boolean; updateId: string | null } {
+  try {
+    return { isEmbeddedLaunch: Updates.isEmbeddedLaunch, updateId: Updates.updateId };
+  } catch {
+    return { isEmbeddedLaunch: false, updateId: null };
+  }
+}
+
+/**
+ * Links to the fixed-language legal pages (see root CLAUDE.md: not localized, always German) plus
+ * the installed app version and current OTA update state, for anyone who needs to reach them without
+ * going through the web app. The OTA suffix exists so a support conversation ("did the update actually
+ * arrive?") can be answered by reading this screen instead of guessing — compare the short id shown
+ * here against the "Android update ID" an `eas update` publish prints.
+ */
 function LegalSection() {
   const { t } = useTranslation();
   const { colors } = useTheme();
   const styles = useMemo(() => makeStyles(colors), [colors]);
   const version = Constants.expoConfig?.version ?? "?";
+  const { isEmbeddedLaunch, updateId } = readOtaUpdateId();
+  const ota = isEmbeddedLaunch
+    ? t("pets.otaEmbedded")
+    : updateId
+      ? t("pets.otaId", { id: updateId.slice(0, 8) })
+      : t("pets.otaUnknown");
 
   const links = [
     { label: t("pets.legalImpressum"), path: "impressum" },
@@ -237,7 +267,7 @@ function LegalSection() {
           <Text style={styles.legalLink}>{link.label}</Text>
         </Pressable>
       ))}
-      <Text style={styles.versionText}>{t("pets.versionLabel", { version })}</Text>
+      <Text style={styles.versionText}>{t("pets.versionLabel", { version, ota })}</Text>
     </View>
   );
 }

mobile/src/i18n/locales/de.json

@@ -209,7 +209,10 @@
     "legalChildSafety": "Kinderschutz",
     "petSuggestionsTitle": "Tier-Vorschläge",
     "petSuggestionsLabel": "Erhalte gelegentlich eine Benachrichtigung zu einem Tier, das dir gefallen könnte.",
-    "versionLabel": "Version {{version}}",
+    "versionLabel": "Version {{version}} - {{ota}}",
+    "otaId": "OTA {{id}}",
+    "otaEmbedded": "Build (kein OTA)",
+    "otaUnknown": "OTA unbekannt",
     "logoutButton": "Abmelden",
     "logoutConfirmTitle": "Abmelden?",
     "logoutConfirmMessage": "Du wirst von deinem Konto abgemeldet und zum Login zurückgeschickt."

mobile/src/i18n/locales/en.json

@@ -209,7 +209,10 @@
     "legalChildSafety": "Child Safety Standards",
     "petSuggestionsTitle": "Pet suggestions",
     "petSuggestionsLabel": "Occasionally get notified about a pet you might like.",
-    "versionLabel": "Version {{version}}",
+    "versionLabel": "Version {{version}} - {{ota}}",
+    "otaId": "OTA {{id}}",
+    "otaEmbedded": "Build (no OTA)",
+    "otaUnknown": "OTA unknown",
     "logoutButton": "Log out",
     "logoutConfirmTitle": "Log out?",
     "logoutConfirmMessage": "You'll be signed out of your account and sent back to the login screen."