G3: F01 — remove asyncio.Future wrap from TCP connect()

TCPConnection.connect() returned a resolved asyncio.Future wrapping
self.host instead of the plain string.  ConnectionManager put this
Future directly into the CONNECTED event payload, which crashed any
downstream serializer (e.g. HA recorder's sanitize_event_data) that
tried to walk the payload dict.  BLE and serial already return plain
strings.  Fix: delete the Future creation and return self.host
directly.

Refs: Forensics report finding F01

src/meshcore/tcp_cx.py

@@ -59,10 +59,7 @@ class TCPConnection:
         )
 
         logger.info("TCP Connection started")
-        future = asyncio.Future()
-        future.set_result(self.host)
-
-        return future
+        return self.host
 
     def set_reader(self, reader):
         self.reader = reader