fix(s7): numeric TSAP loads in form, shared TSAP conflict error, Test Connect read detects PUT/GET disabled, pin Int32 ms rounding (#632 #638)

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.S7.Contracts/S7DriverOptions.cs

@@ -56,6 +56,7 @@ public sealed class S7DriverOptions
     ///     <c>"0100"</c>, <c>"0x0100"</c>). Null/blank keeps S7.Net's per-CPU default (<c>01.00</c>).
     ///     Needed for CPUs / gateways that reserve connection resources by TSAP (S7-400H, CP343, LOGO!).
     /// </summary>
+    [System.Text.Json.Serialization.JsonConverter(typeof(S7TsapJsonConverter))]
     public string? LocalTsap { get; init; }
 
     /// <summary>
@@ -63,6 +64,7 @@ public sealed class S7DriverOptions
     ///     (e.g. <c>"03.01"</c> = S7-basic resource, rack 0 slot 1). Null/blank keeps the slot-derived default.
     ///     Mutually exclusive with <see cref="ConnectionType"/>.
     /// </summary>
+    [System.Text.Json.Serialization.JsonConverter(typeof(S7TsapJsonConverter))]
     public string? RemoteTsap { get; init; }
 
     /// <summary>
@@ -72,6 +74,11 @@ public sealed class S7DriverOptions
     /// </summary>
     public S7ConnectionType? ConnectionType { get; init; }
 
+    /// <summary>The authoring/load error for setting both <see cref="RemoteTsap"/> and <see cref="ConnectionType"/>; shared by the factory and the AdminUI form so they never disagree.</summary>
+    public const string TsapConflictDetail =
+        "sets both RemoteTsap and ConnectionType; ConnectionType only fills the first byte of the " +
+        "slot-derived remote TSAP, so choose one.";
+
     /// <summary>Connect + per-operation timeout.</summary>
     public TimeSpan Timeout { get; init; } = TimeSpan.FromSeconds(5);
 
@@ -160,6 +167,31 @@ public sealed class S7DriverOptions
     public const int DefaultSpanReadMaxSpanBytes = 220;
 }
 
+/// <summary>
+///     Reads a TSAP as either hex text (<c>"03.01"</c>) or a JSON number (<c>769</c>, the form the driver
+///     factory also accepts) and always writes the hex text. Without it a numeric TSAP would fail to bind to
+///     the string property, and a typed consumer (the AdminUI form, the Test Connect probe) would fall back
+///     to defaults — a form Save would then silently erase the authored config.
+/// </summary>
+public sealed class S7TsapJsonConverter : System.Text.Json.Serialization.JsonConverter<string?>
+{
+    /// <inheritdoc />
+    public override string? Read(ref System.Text.Json.Utf8JsonReader reader, Type typeToConvert, System.Text.Json.JsonSerializerOptions options)
+    {
+        if (reader.TokenType == System.Text.Json.JsonTokenType.Null) return null;
+        if (reader.TokenType == System.Text.Json.JsonTokenType.Number && reader.TryGetUInt16(out var n))
+            return $"{n >> 8:X2}.{n & 0xFF:X2}";
+        if (reader.TokenType == System.Text.Json.JsonTokenType.String) return reader.GetString();
+        throw new System.Text.Json.JsonException("S7 TSAP must be hex text such as \"03.01\" or a 16-bit number.");
+    }
+
+    /// <inheritdoc />
+    public override void Write(System.Text.Json.Utf8JsonWriter writer, string? value, System.Text.Json.JsonSerializerOptions options)
+    {
+        if (value is null) writer.WriteNullValue(); else writer.WriteStringValue(value);
+    }
+}
+
 public sealed class S7ProbeOptions
 {
     /// <summary>Gets or sets a value indicating whether probing is enabled.</summary>