fix: stub is_radio_zombie in flood scope test mock

The send_channel_message test was leaving bot.is_radio_zombie as an
unset MagicMock attribute, which evaluates truthy and triggers the
zombie-state early return before flood scope logic runs.

Add bot.is_radio_zombie = False to the mock setup so the function
reaches the set_flood_scope call as intended.

tests/integration/test_flood_scope_reply.py

@@ -299,6 +299,7 @@ async def test_send_channel_message_normalizes_bare_scope():
     bot.config = make_config()
     bot.connected = True
     bot.meshcore = MagicMock()
+    bot.is_radio_zombie = False
     bot.channel_manager = MagicMock()
     bot.channel_manager.get_channel_number = Mock(return_value=0)