feat(mobile): add x-device-language to hono headers (#195)

apps/mobile/lib/client.ts

@@ -1,6 +1,7 @@
 import type { AppType } from '@6pm/api'
 import { getClerkInstance } from '@clerk/clerk-expo'
 import { QueryClient } from '@tanstack/react-query'
+import { getLocales } from 'expo-localization'
 import { hc } from 'hono/client'
 import { tokenCache } from './cache'
 
@@ -11,11 +12,20 @@ export const clerk = getClerkInstance({
 
 export const getHonoClient = async () => {
   const token = await clerk.session?.getToken()
+  const deviceLanguage = getLocales()[0].languageCode
+
+  const headers: Record<string, string> = {}
+
+  if (token) {
+    headers.Authorization = `Bearer ${token}`
+  }
+
+  if (deviceLanguage) {
+    headers['x-device-language'] = deviceLanguage
+  }
+
   return hc<AppType>(process.env.EXPO_PUBLIC_API_URL!, {
-    headers: {
-      // biome-ignore lint/style/useNamingConvention: <explanation>
-      Authorization: `Bearer ${token}`,
-    },
+    headers,
   })
 }