♻️(frontend) refactor the username storage

Create a new dedicated store for user choices, starting with the
username, to decouple this part from any LiveKit elements. This is
better for tree-shaking, and depending on LiveKit for storing the
username brings no real value.

The refactoring will be continued later for the other user choices
that can be persisted.

src/frontend/src/features/home/components/CreateMeetingMenu.tsx

@@ -9,10 +9,11 @@ import { useState } from 'react'
 
 import { menuRecipe } from '@/primitives/menuRecipe'
 import { ApiRoom } from '@/features/rooms/api/ApiRoom'
-import { loadUserChoices } from '@livekit/components-core'
+import { useSnapshot } from 'valtio'
+import { userStore } from '@/stores/user'
 
 export const CreateMeetingMenu = () => {
-  const { username } = loadUserChoices()
+  const { username } = useSnapshot(userStore)
 
   const { t } = useTranslation('home')
   const { mutateAsync: createRoom } = useCreateRoom()

src/frontend/src/features/rooms/components/Conference.tsx

@@ -36,6 +36,7 @@ import { PictureInPictureConference } from '@/features/pip/components/PictureInP
 import { notifyAutoMutedOnJoin } from '@/features/notifications/utils'
 import { useSnapshot } from 'valtio'
 import { userPreferencesStore } from '@/stores/userPreferences'
+import { userStore } from '@/stores/user'
 
 export const Conference = ({
   roomId,
@@ -53,6 +54,8 @@ export const Conference = ({
     userChoices: LocalUserChoices
   }
 
+  const { username } = useSnapshot(userStore)
+
   useEffect(() => {
     posthog.capture('visit-room', { slug: roomId })
   }, [roomId, posthog])
@@ -83,10 +86,10 @@ export const Conference = ({
     queryFn: () =>
       fetchRoom({
         roomId: roomId as string,
-        username: userConfig.username,
+        username: username,
       }).catch((error) => {
         if (error.statusCode == '404') {
-          createRoom({ slug: roomId, username: userConfig.username })
+          createRoom({ slug: roomId, username })
         }
       }),
     retry: false,

src/frontend/src/features/rooms/components/Join.tsx

@@ -42,12 +42,13 @@ import {
   saveAudioInputDeviceId,
   saveAudioInputEnabled,
   saveAudioOutputDeviceId,
-  saveUsername,
   saveVideoInputDeviceId,
   saveVideoInputEnabled,
   userChoicesStore,
 } from '@/stores/userChoices'
 
+import { saveUsername, userStore } from '@/stores/user'
+
 import { useCannotUseDevice } from '../livekit/hooks/useCannotUseDevice'
 import { useSnapshot } from 'valtio'
 
@@ -121,9 +122,10 @@ export const Join = ({
     audioOutputDeviceId,
     videoDeviceId,
     processorConfig,
-    username,
   } = useSnapshot(userChoicesStore)
 
+  const { username } = useSnapshot(userStore)
+
   const initialUserChoices = useRef<LocalUserChoices | null>(null)
 
   if (initialUserChoices.current === null) {
@@ -134,7 +136,6 @@ export const Join = ({
       audioOutputDeviceId,
       videoDeviceId,
       processorConfig,
-      username,
     }
   }
 

src/frontend/src/features/settings/components/tabs/AccountTab.tsx

@@ -8,7 +8,7 @@ import { HStack } from '@/styled-system/jsx'
 import { useState } from 'react'
 import { LoginButton } from '@/components/LoginButton'
 import { useRenameParticipant } from '@/features/rooms/api/renameParticipant'
-import { saveUsername } from '@/stores/userChoices'
+import { saveUsername } from '@/stores/user'
 import { logout } from '@/features/auth/utils/logout'
 
 export type AccountTabProps = Pick<DialogProps, 'onOpenChange'> &

src/frontend/src/stores/user.ts

@@ -0,0 +1,37 @@
+import { proxy, subscribe } from 'valtio'
+import { STORAGE_KEYS } from '@/utils/storageKeys'
+
+type State = {
+  username: string
+}
+
+const DEFAULT_STATE = {
+  username: '',
+}
+
+function getUserState(): State {
+  try {
+    const stored = localStorage.getItem(STORAGE_KEYS.USER)
+    if (!stored) return DEFAULT_STATE
+    const parsed = JSON.parse(stored)
+    return {
+      ...parsed,
+    }
+  } catch (error: unknown) {
+    console.error(
+      '[UserPreferencesStore] Failed to parse stored settings:',
+      error
+    )
+    return DEFAULT_STATE
+  }
+}
+
+export const userStore = proxy<State>(getUserState())
+
+subscribe(userStore, () => {
+  localStorage.setItem(STORAGE_KEYS.USER, JSON.stringify(userStore))
+})
+
+export const saveUsername = (username: string) => {
+  userStore.username = username
+}

src/frontend/src/stores/userChoices.ts

@@ -12,7 +12,7 @@ import { VideoQuality } from 'livekit-client'
 
 export type VideoResolution = 'h720' | 'h360' | 'h180'
 
-export type LocalUserChoices = LocalUserChoicesLK & {
+export type LocalUserChoices = Omit<LocalUserChoicesLK, 'username'> & {
   processorConfig?: ProcessorConfig
   noiseReductionEnabled?: boolean
   audioOutputDeviceId?: string
@@ -32,7 +32,13 @@ function getUserChoicesState(): LocalUserChoices {
 
 export const userChoicesStore = proxy<LocalUserChoices>(getUserChoicesState())
 subscribe(userChoicesStore, () => {
-  saveUserChoices(userChoicesStore, false)
+  // TEMPORARY: cast needed because our store omits `username`, which we no
+  // longer persis in this store, while LiveKit's `saveUserChoices` still expects the full
+  // `LocalUserChoices` shape. `username` ends up `undefined` in the saved
+  // object, which `saveUserChoices` tolerates at runtime.
+  // We are migrating away from LiveKit's persistence logic to our own store
+  // handling for more control — this cast can be removed once that lands.
+  saveUserChoices(userChoicesStore as LocalUserChoicesLK, false)
 })
 
 // we run some logic on store loading to check if the processor config is still valid
@@ -90,10 +96,6 @@ export const saveVideoSubscribeQuality = (quality: VideoQuality) => {
   userChoicesStore.videoSubscribeQuality = quality
 }
 
-export const saveUsername = (username: string) => {
-  userChoicesStore.username = username
-}
-
 export const saveNoiseReductionEnabled = (enabled: boolean) => {
   userChoicesStore.noiseReductionEnabled = enabled
 }

src/frontend/src/utils/storageKeys.tsx

@@ -4,5 +4,6 @@
 export const STORAGE_KEYS = {
   NOTIFICATIONS: 'app_notification_settings',
   USER_PREFERENCES: 'app_user_preferences',
+  USER: 'app_user',
   ACCESSIBILITY: 'app_accessibility_settings',
 } as const