refactor(historian): single-parse ExtractTagHistorize + review-nit tests/docs

Stop parsing TagConfig twice per tag on the deploy hot path: Phase7Composer's
equipment-tag Select lambda is now block-bodied (captures isHistorized/historianTagname
once), and DeploymentArtifact.BuildEquipmentTagPlans captures locals before result.Add.
Add wrong-type-historianTagname InlineData to ExtractTagHistorizeTests. Extend the
parity round-trip fixture with a 4th tag (isHistorized:false + JSON-null tagname)
exercising the artifact-side private guard path. Align DeploymentArtifact's
ExtractTagHistorize doc-comment with the composer-side phrasing (ExtractTagFullName /
ExtractTagAlarm cross-reference).

src/Server/ZB.MOM.WW.OtOpcUa.Runtime/Drivers/DeploymentArtifact.cs

@@ -437,6 +437,7 @@ public static class DeploymentArtifact
             // ordinary equipment tags now (GalaxyMxGateway is a standard Equipment-kind driver).
             if (!equipmentNamespaces.Contains(nsId)) continue;
 
+            var (isHistorized, historianTagname) = ExtractTagHistorize(tagConfig);
             result.Add(new EquipmentTagPlan(
                 TagId: tagId!,
                 EquipmentId: equipmentId!,
@@ -447,8 +448,8 @@ public static class DeploymentArtifact
                 FullName: ExtractTagFullName(tagConfig),
                 Writable: writable,
                 Alarm: ExtractTagAlarm(tagConfig),
-                IsHistorized: ExtractTagHistorize(tagConfig).IsHistorized,
-                HistorianTagname: ExtractTagHistorize(tagConfig).HistorianTagname));
+                IsHistorized: isHistorized,
+                HistorianTagname: historianTagname));
         }
 
         result.Sort((a, b) =>
@@ -678,7 +679,8 @@ public static class DeploymentArtifact
     /// the <c>isHistorized</c> bool (absent / not a bool / non-object root / blank / malformed ⇒
     /// <c>false</c>) and the optional <c>historianTagname</c> string override (absent / not a string /
     /// whitespace-or-empty ⇒ <c>null</c>, meaning the historian tagname defaults to the tag's FullName,
-    /// resolved later). The raw string value is used — not trimmed. Never throws. The live-edit side
+    /// resolved later). The raw string value is used — not trimmed — matching <c>ExtractTagFullName</c> /
+    /// <c>ExtractTagAlarm</c>. Never throws. The live-edit side
     /// (<c>Phase7Composer.ExtractTagHistorize</c>) MUST parse identically (byte-parity).</summary>
     private static (bool IsHistorized, string? HistorianTagname) ExtractTagHistorize(string? tagConfig)
     {