flip types/bsky sources to #/lexicons, add chat client and strict hook contracts

Phase 3 task 2: types/bsky sibling modules (post/profile/starterPack) now
source from generated #/lexicons with interim dual-world widening aliases
(TODO(phase4) markers). SessionBundle gains a chatClient proxied to
did:web:api.bsky.chat#bsky_chat via useChatClient(). usePdsClient() and
useChatClient() no longer fall back to the public appview when logged out -
they return a client that throws NotAuthenticatedError before any network
I/O; useMaybePdsClient()/useMaybeChatClient() cover logged-out-aware
callers. RichText pilot: useRichText.ts on @bsky.app/sdk/richtext with
detectFacets(pdsClient); RichText.tsx display sink accepts both worlds.

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

src/components/hooks/useRichText.ts

@@ -1,13 +1,20 @@
 import {useEffect, useState} from 'react'
-import {RichText as RichTextAPI} from '@atproto/api'
+import {RichText as RichTextAPI} from '@bsky.app/sdk/richtext'
 
-import {useAgent} from '#/state/session'
+import {usePdsClient} from '#/state/session'
 
 export function useRichText(text: string): [RichTextAPI, boolean] {
   const [prevText, setPrevText] = useState(text)
   const [rawRT, setRawRT] = useState(() => new RichTextAPI({text}))
   const [resolvedRT, setResolvedRT] = useState<RichTextAPI | null>(null)
-  const agent = useAgent()
+  /*
+   * Facet detection resolves handles via `com.atproto.identity.resolveHandle`,
+   * which the account (PDS) client serves. We standardize on the account client
+   * where a session is in scope (design section B). Logged out, this is the
+   * throwing client; `detectFacets` will reject, and the raw (unresolved)
+   * RichText is returned in the meantime.
+   */
+  const client = usePdsClient()
   if (text !== prevText) {
     setPrevText(text)
     setRawRT(new RichTextAPI({text}))
@@ -19,7 +26,7 @@ export function useRichText(text: string): [RichTextAPI, boolean] {
     async function resolveRTFacets() {
       // new each time
       const resolvedRT = new RichTextAPI({text})
-      await resolvedRT.detectFacets(agent)
+      await resolvedRT.detectFacets(client)
       if (!ignore) {
         setResolvedRT(resolvedRT)
       }
@@ -28,7 +35,7 @@ export function useRichText(text: string): [RichTextAPI, boolean] {
     return () => {
       ignore = true
     }
-  }, [text, agent])
+  }, [text, client])
   const isResolving = resolvedRT === null
   return [resolvedRT ?? rawRT, isResolving]
 }