Add curses dashboard and XIAO bridge examples; enhance stream parser for UTF-8 logging

tests/test_micromesh.py

@@ -77,6 +77,12 @@ class MicroMeshTests(unittest.TestCase):
         self.assertEqual(packets, [b"one", b"two"])
         self.assertEqual(logs, ["debug line"])
 
+    def test_stream_parser_sanitizes_invalid_utf8_logs(self):
+        logs = []
+        parser = StreamParser(on_log=logs.append)
+        self.assertEqual(parser.feed(b"bad:\xff\xfe\n"), [])
+        self.assertEqual(logs, ["bad:??"])
+
     def test_send_text_builds_to_radio_frame(self):
         import micromesh.interface as interface_module
         old_packet_id = interface_module._packet_id