refactor: add Pubkey, Privkey, NoteId string aliases

This is a non-behavioral change in preparation for the actual switchover
from Strings to Ids. The purpose of this kit is to reduce the size of
the switchover commit which is going to be very large.

damus/Views/Profile/ProfileName.swift

@@ -12,7 +12,7 @@ enum FriendType {
     case fof
 }
 
-func get_friend_type(contacts: Contacts, pubkey: String) -> FriendType? {
+func get_friend_type(contacts: Contacts, pubkey: Pubkey) -> FriendType? {
     if contacts.is_friend_or_self(pubkey) {
         return .friend
     }
@@ -26,7 +26,7 @@ func get_friend_type(contacts: Contacts, pubkey: String) -> FriendType? {
 
 struct ProfileName: View {
     let damus_state: DamusState
-    let pubkey: String
+    let pubkey: Pubkey
     let profile: Profile?
     let prefix: String
     
@@ -36,7 +36,7 @@ struct ProfileName: View {
     @State var nip05: NIP05?
     @State var donation: Int?
     
-    init(pubkey: String, profile: Profile?, prefix: String = "", damus: DamusState, show_nip5_domain: Bool = true) {
+    init(pubkey: Pubkey, profile: Profile?, prefix: String = "", damus: DamusState, show_nip5_domain: Bool = true) {
         self.pubkey = pubkey
         self.profile = profile
         self.prefix = prefix