refactor: api_types/buttons: Use RESOLVED_TOPIC_PREFIX as in server.

This both renames the constant in use from RESOLVED_PREFIX, but also
combines the prefix single character value with a space - as both used
in the backend and frontend on the Zulip server.

Author: neiljp

zulipterminal/api_types.py

@@ -3,7 +3,8 @@
 from typing_extensions import Literal, TypedDict
 
 
-RESOLVED_PREFIX = "✔"
+RESOLVED_TOPIC_PREFIX = "✔ "
+
 EditPropagateMode = Literal["change_one", "change_all", "change_later"]
 EmojiType = Literal["realm_emoji", "unicode_emoji", "zulip_extra_emoji"]
 # Limited flags which could be present in update_message_flag events.

zulipterminal/ui_tools/buttons.py

@@ -6,7 +6,7 @@
 import urwid
 from typing_extensions import TypedDict
 
-from zulipterminal.api_types import RESOLVED_PREFIX, EditPropagateMode
+from zulipterminal.api_types import RESOLVED_TOPIC_PREFIX, EditPropagateMode
 from zulipterminal.config.keys import is_command_key, primary_key_for_command
 from zulipterminal.config.regexes import REGEX_INTERNAL_LINK_STREAM_ID
 from zulipterminal.config.symbols import (
@@ -301,7 +301,7 @@ def __init__(
         # The space acts as a TopButton prefix and gives an effective 3 spaces for unresolved topics.
         topic_prefix = " "
         topic_name = self.topic_name
-        if self.topic_name.startswith(RESOLVED_PREFIX + " "):
+        if self.topic_name.startswith(RESOLVED_TOPIC_PREFIX):
             topic_prefix = self.topic_name[:1]
             topic_name = self.topic_name[2:]