Auto: s7-c4 — deadband / on-change with thresholds

Closes #297

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

@@ -253,6 +253,21 @@ public sealed class S7ProbeOptions
 ///     (legacy single-rate behaviour). Group names are matched case-insensitively. See
 ///     <c>docs/v2/s7.md</c> "Per-tag scan groups" section.
 /// </param>
+/// <param name="DeadbandAbsolute">
+///     PR-S7-C4 — optional absolute change threshold for numeric tags. When set the driver
+///     suppresses <c>OnDataChange</c> publishes whose <c>|new - prev|</c> is strictly less
+///     than this value. Ignored for non-numeric types (string, bool, byte[]) which keep
+///     exact-equality semantics. NaN / ±Infinity samples bypass the filter and always
+///     publish. See <c>docs/v2/s7.md</c> "Deadband / on-change" section.
+/// </param>
+/// <param name="DeadbandPercent">
+///     PR-S7-C4 — optional percent-of-baseline change threshold for numeric tags
+///     (0..100; e.g. <c>10</c> = "publish when |delta| ≥ 10% of |prev|"). Falls back to
+///     <see cref="DeadbandAbsolute"/> when <c>|prev| &lt; 1e-6</c> (near-zero baseline rule)
+///     to avoid div-by-zero / divergence; if no absolute is configured the sample publishes.
+///     When both deadbands are set the filters are OR'd — the value publishes if EITHER
+///     threshold says publish (Kepware-style semantics). See <c>docs/v2/s7.md</c>.
+/// </param>
 public sealed record S7TagDefinition(
     string Name,
     string Address,
@@ -261,7 +276,9 @@ public sealed record S7TagDefinition(
     int StringLength = 254,
     bool WriteIdempotent = false,
     int? ElementCount = null,
-    string? ScanGroup = null);
+    string? ScanGroup = null,
+    double? DeadbandAbsolute = null,
+    double? DeadbandPercent = null);
 
 public enum S7DataType
 {