Restore contacts from backup

XXClient library

• Improve error handling in UdMultiLookupCallback.

xx-messenger example

• Improve backup restoration.
• Restore contacts.
• Add contact lookup feature.
• Display contact ids.
• Improve sending requests.
• Restore username from restored facts, not from restored params.

Examples/xx-messenger/Sources/AppFeature/AppEnvironment+Live.swift

@@ -4,6 +4,7 @@ import ChatFeature
 import CheckContactAuthFeature
 import ConfirmRequestFeature
 import ContactFeature
+import ContactLookupFeature
 import ContactsFeature
 import Foundation
 import HomeFeature
@@ -38,7 +39,11 @@ extension AppEnvironment {
       mainQueue: mainQueue,
       bgQueue: bgQueue,
       lookup: {
-        ContactLookupEnvironment()
+        ContactLookupEnvironment(
+          messenger: messenger,
+          mainQueue: mainQueue,
+          bgQueue: bgQueue
+        )
       },
       sendRequest: {
         SendRequestEnvironment(