Don't have local echoes stay fixed at the bottom

TODO.md

@@ -47,6 +47,7 @@
   - Event delegates changing height don't scroll the list
   - When selecting text and scrolling up, selection stops working after a while
     - Ensure all the text that should be copied is copied
+    - Multiple messages are currently copied out of order
 
   - Pressing backspace in composer sometimes doesn't work
   - Message order isn't preserved when sending a first message in a E2E

src/python/models/items.py

@@ -148,12 +148,6 @@ class Event(ModelItem):
 
     def __lt__(self, other: "Event") -> bool:
         # Sort events from newest to oldest. return True means return False.
-        # Local echoes always stay first.
-        if self.is_local_echo and not other.is_local_echo:
-            return True
-        if other.is_local_echo and not self.is_local_echo:
-            return False
-
         return self.date > other.date
 
     @property