nostrdb: add profiles to nostrdb

This adds profiles to nostrdb

- Remove in-memory Profiles caches, nostrdb is as fast as an in-memory cache
- Remove ProfileDatabase and just use nostrdb directly

Changelog-Changed: Use nostrdb for profiles

damus/Views/SaveKeysView.swift

@@ -10,7 +10,7 @@ import Security
 
 struct SaveKeysView: View {
     let account: CreateAccountModel
-    let pool: RelayPool = RelayPool()
+    let pool: RelayPool = RelayPool(ndb: Ndb()!)
     @State var pub_copied: Bool = false
     @State var priv_copied: Bool = false
     @State var loading: Bool = false