feat(lmxproxy): phase 1 — v2 protocol types and domain model

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lmxproxy/src-reference/ZB.MOM.WW.LmxProxy.Client/Domain/Vtq.cs

@@ -0,0 +1,27 @@
+using System;
+
+namespace ZB.MOM.WW.LmxProxy.Client.Domain;
+
+/// <summary>
+/// Value, Timestamp, and Quality structure for SCADA data.
+/// </summary>
+/// <param name="Value">The value.</param>
+/// <param name="Timestamp">The timestamp when the value was read.</param>
+/// <param name="Quality">The quality of the value.</param>
+public readonly record struct Vtq(object? Value, DateTime Timestamp, Quality Quality)
+{
+	/// <summary>Creates a new VTQ with the specified value and quality, using the current UTC timestamp.</summary>
+	public static Vtq New(object? value, Quality quality) => new(value, DateTime.UtcNow, quality);
+
+	/// <summary>Creates a new VTQ with the specified value, timestamp, and quality.</summary>
+	public static Vtq New(object? value, DateTime timestamp, Quality quality) => new(value, timestamp, quality);
+
+	/// <summary>Creates a Good-quality VTQ with the current UTC time.</summary>
+	public static Vtq Good(object? value) => new(value, DateTime.UtcNow, Quality.Good);
+
+	/// <summary>Creates a Bad-quality VTQ with the current UTC time.</summary>
+	public static Vtq Bad(object? value = null) => new(value, DateTime.UtcNow, Quality.Bad);
+
+	/// <summary>Creates an Uncertain-quality VTQ with the current UTC time.</summary>
+	public static Vtq Uncertain(object? value) => new(value, DateTime.UtcNow, Quality.Uncertain);
+}