finish phase 3: type-only codemod and zero non-bridge @atproto/api imports

Task 8: codemod repointed 150 namespace-type files to #/lexicons
(AppBskyFeedDefs.PostView -> app.bsky.feed.defs.PostView, .Record -> .Main)
plus ~105 hand-fixed consumers (composer/video state, DebugMod, Profile,
onboarding, dialogs). DM_SERVICE_HEADERS deleted; last chat call sites on
the chat client. RichText.tsx flipped to SDK-only. Remaining @atproto/api
importers: the three session bridge files, the deliberate dual-world
matcher in lib/xrpc-error.ts, and test fixtures. toLex boundary casts are
TODO(phase4)-tagged for bridge removal.

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

src/screens/Profile/Header/DisplayName.tsx

@@ -1,5 +1,4 @@
 import {View} from 'react-native'
-import {type AppBskyActorDefs} from '@atproto/api'
 import {type ModerationDecision} from '@bsky.app/sdk/moderation'
 
 import {sanitizeDisplayName} from '#/lib/strings/display-names'
@@ -8,12 +7,13 @@ import {type Shadow} from '#/state/cache/types'
 import {atoms as a, platform, useBreakpoints, useTheme} from '#/alf'
 import {ProfileBadges} from '#/components/ProfileBadges'
 import {Text} from '#/components/Typography'
+import {type app} from '#/lexicons'
 
 export function ProfileHeaderDisplayName({
   profile,
   moderation,
 }: {
-  profile: Shadow<AppBskyActorDefs.ProfileViewDetailed>
+  profile: Shadow<app.bsky.actor.defs.ProfileViewDetailed>
   moderation: ModerationDecision
 }) {
   const t = useTheme()