survive session-bundle rebuild in chat, feeds, prefs, and age assurance

Review fixes (PR #11182 round 2). Client identity is no longer stable
across token refresh - on web, a cross-tab sync rebuilds the bundle and
disposes the old clients (whose fetch now throws) - so anything that
captured a client at construction time must re-point at the live one:

- MessagesEventBus and Convo get updateClient(); providers sync it via
  effect. No remount, so poll cursors and optimistic pendingMessages
  survive.
- FeedAPI implementations get setClient(); the post-feed queryFn and
  pollLatest re-point page-held apis before fetching (Merge/Home apis
  are stateful across pages, so they cannot be rebuilt per fetch).
- usePreferencesQuery applies fetched labeler dids to the live appview
  client (applyLabelersToClient, factored from session/moderation),
  restoring the old BskyAgent.getPreferences header side effect.
- ageAssurance redirect overlay/dialog polling is mount-only with
  render-synced refs; a client swap mid-poll no longer latches the
  unmounted flag and strands the overlay.
- Convo message-failure classification defers to lex's shouldRetry()
  instead of treating all status-less errors as recoverable.

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

src/lib/api/feed/author.ts

@@ -19,6 +19,10 @@ export class AuthorFeedAPI implements FeedAPI {
     this._params = feedParams
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   get params() {
     const params = {...this._params}
     params.includePins = params.filter === 'posts_and_author_threads'

src/lib/api/feed/custom.ts

@@ -37,6 +37,10 @@ export class CustomFeedAPI implements FeedAPI {
     this.userInterests = userInterests
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   async peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost> {
     const contentLangs = getContentLanguages().join(',')
     const res = await this.client.call(

src/lib/api/feed/demo.ts

@@ -11,6 +11,10 @@ export class DemoFeedAPI implements FeedAPI {
     this.client = client
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   // eslint-disable-next-line @typescript-eslint/require-await
   async peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost> {
     return DEMO_FEED.feed[0]

src/lib/api/feed/following.ts

@@ -10,6 +10,10 @@ export class FollowingFeedAPI implements FeedAPI {
     this.client = client
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   async peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost> {
     const res = await this.client.call(app.bsky.feed.getTimeline, {
       limit: 1,

src/lib/api/feed/home.ts

@@ -56,6 +56,12 @@ export class HomeFeedAPI implements FeedAPI {
     this.userInterests = userInterests
   }
 
+  setClient(client: Client) {
+    this.client = client
+    this.following.setClient(client)
+    this.discover.setClient(client)
+  }
+
   reset() {
     this.following = new FollowingFeedAPI({client: this.client})
     this.discover = new CustomFeedAPI({

src/lib/api/feed/likes.ts

@@ -18,6 +18,10 @@ export class LikesFeedAPI implements FeedAPI {
     this.params = feedParams
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   async peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost> {
     const res = await this.client.call(app.bsky.feed.getActorLikes, {
       ...this.params,

src/lib/api/feed/list.ts

@@ -18,6 +18,10 @@ export class ListFeedAPI implements FeedAPI {
     this.params = feedParams
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   async peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost> {
     const res = await this.client.call(app.bsky.feed.getListFeed, {
       ...this.params,

src/lib/api/feed/merge.ts

@@ -64,6 +64,14 @@ export class MergeFeedAPI implements FeedAPI {
     })
   }
 
+  setClient(client: Client) {
+    this.client = client
+    this.following.setClient(client)
+    for (const feed of this.customFeeds) {
+      feed.setClient(client)
+    }
+  }
+
   reset() {
     this.following = new MergeFeedSource_Following({
       client: this.client,
@@ -203,6 +211,10 @@ class MergeFeedSource {
     this.feedTuners = feedTuners
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   get numReady() {
     return this.queue.length
   }

src/lib/api/feed/posts.ts

@@ -27,6 +27,10 @@ export class PostListFeedAPI implements FeedAPI {
     }
   }
 
+  setClient(client: Client) {
+    this.client = client
+  }
+
   async peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost> {
     if (this.peek) return this.peek
     throw new Error('Has not fetched yet')

src/lib/api/feed/types.ts

@@ -1,3 +1,5 @@
+import {type Client} from '@atproto/lex-client'
+
 import {type app} from '#/lexicons'
 
 export interface FeedAPIResponse {
@@ -6,6 +8,13 @@ export interface FeedAPIResponse {
 }
 
 export interface FeedAPI {
+  /**
+   * Swap in a fresh client. Feed pages retain their FeedAPI across paginations,
+   * so the client captured at construction goes stale after a session-bundle
+   * rebuild (web cross-tab token sync). Callers re-point the api at the current
+   * client before each fetch/peek so a disposed client is never used.
+   */
+  setClient(client: Client): void
   peekLatest(): Promise<app.bsky.feed.defs.FeedViewPost>
   fetch({
     cursor,