Initial commit: Dabit Time Manager project

Python-based time management application with UDP discovery,
TCP protocol communication, time sync, and drift monitoring.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

models/reading.py

@@ -0,0 +1,20 @@
+"""TimeReading 데이터클래스"""
+
+from dataclasses import dataclass
+from datetime import datetime
+
+
+@dataclass
+class TimeReading:
+    """시간 읽기 결과"""
+    controller_mac: str
+    controller_label: str
+    pc_time: datetime
+    controller_time: datetime
+    drift_seconds: float
+
+    @property
+    def drift_display(self) -> str:
+        """오차 표시용 문자열"""
+        sign = "+" if self.drift_seconds >= 0 else ""
+        return f"{sign}{self.drift_seconds:.1f}초"