add composer local sources and convo members

src/features/autocomplete/useConvoMembersSource.ts

@@ -0,0 +1,26 @@
+import {useConvo} from '#/state/messages/convo'
+import {useSession} from '#/state/session'
+import {type LocalSource} from '#/components/Autocomplete/types'
+
+/**
+ * Members of the active conversation as an autocomplete LocalSource, so the
+ * mention typeahead in a chat prioritizes the people in it. Must be used
+ * within a ConvoProvider.
+ */
+export function useConvoMembersSource(): LocalSource {
+  const convo = useConvo()
+  const {currentAccount} = useSession()
+  const members = convo.convo?.members ?? []
+
+  return {
+    key: 'convo-members',
+    items: members
+      .filter(member => member.did !== currentAccount?.did)
+      .map(member => ({
+        key: member.did,
+        type: 'profile' as const,
+        value: '@' + member.handle,
+        profile: member,
+      })),
+  }
+}