mute: integrate new MutelistManager

This patch is slightly large (I think still within the guidelines tho) ,
but also pretty straightforward. I thought for a while about how I could
split this up in a straightforward way, and I couldn’t come up with
anything without breaking intermediate builds.

- Deleted a lot of old/unnecessary code (ie. the Collection extension
  for MuteItem, since we’re now using the MutelistManager sets)

- Changed damus_state.contacts to damus_state.mutelist_manager for all
  mute list manager work

- Updated MutelistView to take advantage of new code (this is probably
  the largest change in this patch)

Lighting-Address: fishcharlie@strike.me
Signed-off-by: Charlie Fish <contact@charlie.fish>
Reviewed-by: William Casarin <jb55@jb55.com>
Link: 20240210163650.42884-4-contact@charlie.fish
Signed-off-by: William Casarin <jb55@jb55.com>

damus/Models/MutedThreadsManager.swift

@@ -30,9 +30,9 @@ func migrate_old_muted_threads_to_new_mutelist(keypair: Keypair, damus_state: Da
     let mutedThreads = loadOldMutedThreads(pubkey: fullKeypair.pubkey)
     guard !mutedThreads.isEmpty else { return }
     // Set new muted system for those existing threads
-    let previous_mute_list_event = damus_state.contacts.mutelist
+    let previous_mute_list_event = damus_state.mutelist_manager.event
     guard let new_mutelist_event = create_or_update_mutelist(keypair: fullKeypair, mprev: previous_mute_list_event, to_add: Set(mutedThreads.map { MuteItem.thread($0, nil) })) else { return }
-    damus_state.contacts.set_mutelist(new_mutelist_event)
+    damus_state.mutelist_manager.set_mutelist(new_mutelist_event)
     damus_state.postbox.send(new_mutelist_event)
     // Set existing muted threads to an empty array
     UserDefaults.standard.set([], forKey: getMutedThreadsKey(pubkey: keypair.pubkey))