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/state/queries/profile.ts

@@ -275,7 +275,7 @@ export function useProfileFollowMutationQueue(
           did,
         })
         userActionHistory.follow([did])
-        return uri
+        return uri as AtUriString
       } else {
         if (prevFollowingUri) {
           await unfollowMutation.mutateAsync({
@@ -337,7 +337,7 @@ export function useProfileFollowMutationQueue(
       if (finalFollowingUri) {
         void client
           .call(app.bsky.graph.getSuggestedFollowsByActor, {
-            actor: did as AtIdentifierString,
+            actor: did,
           })
           .then(res => {
             const dids = res.suggestions
@@ -516,7 +516,7 @@ export function useProfileBlockMutationQueue(
           did,
         })
         ax.metric('profile:block', {})
-        return uri
+        return uri as AtUriString
       } else {
         if (prevBlockUri) {
           await unblockMutation.mutateAsync({