Improve typeahead search with inclusion of followed users (temporary solution) (#1612)

* Update follows cache to maintain some user info

* Prioritize follows in composer autocomplete

* Clean up logic and add new autocomplete to search

* Update follow hook

src/lib/hooks/useFollowProfile.ts

@@ -0,0 +1,54 @@
+import React from 'react'
+import {AppBskyActorDefs} from '@atproto/api'
+import {useStores} from 'state/index'
+import {FollowState} from 'state/models/cache/my-follows'
+
+export function useFollowProfile(profile: AppBskyActorDefs.ProfileViewBasic) {
+  const store = useStores()
+  const state = store.me.follows.getFollowState(profile.did)
+
+  return {
+    state,
+    following: state === FollowState.Following,
+    toggle: React.useCallback(async () => {
+      if (state === FollowState.Following) {
+        try {
+          await store.agent.deleteFollow(
+            store.me.follows.getFollowUri(profile.did),
+          )
+          store.me.follows.removeFollow(profile.did)
+          return {
+            state: FollowState.NotFollowing,
+            following: false,
+          }
+        } catch (e: any) {
+          store.log.error('Failed to delete follow', e)
+          throw e
+        }
+      } else if (state === FollowState.NotFollowing) {
+        try {
+          const res = await store.agent.follow(profile.did)
+          store.me.follows.addFollow(profile.did, {
+            followRecordUri: res.uri,
+            did: profile.did,
+            handle: profile.handle,
+            displayName: profile.displayName,
+            avatar: profile.avatar,
+          })
+          return {
+            state: FollowState.Following,
+            following: true,
+          }
+        } catch (e: any) {
+          store.log.error('Failed to create follow', e)
+          throw e
+        }
+      }
+
+      return {
+        state: FollowState.Unknown,
+        following: false,
+      }
+    }, [store, profile, state]),
+  }
+}