test(historian): assert Deferred sink forwards historianTagname + doc nits

I1: DeferredAddressSpaceSinkTests.RecordingSink now captures HistorianTagname
per EnsureVariable call (HistorianQueue/HistorianCalls, matching the
Phase7ApplierTests pattern); new test EnsureVariable_forwards_historianTagname_to_inner_sink
asserts the arg is forwarded unchanged through DeferredAddressSpaceSink.

M1: OtOpcUaNodeManager.EnsureVariable doc-comment notes that a changed
historize intent on an already-registered node is silently ignored until
a RebuildAddressSpace (rebuild precondition for Task 3 implementers).

N2: DeploymentArtifact.ExtractTagHistorize doc wording: "The live-edit
side" → "The live-edit composer side".

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

@@ -680,7 +680,7 @@ public static class DeploymentArtifact
     /// <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 — matching <c>ExtractTagFullName</c> /
-    /// <c>ExtractTagAlarm</c>. Never throws. The live-edit side
+    /// <c>ExtractTagAlarm</c>. Never throws. The live-edit composer side
     /// (<c>Phase7Composer.ExtractTagHistorize</c>) MUST parse identically (byte-parity).</summary>
     private static (bool IsHistorized, string? HistorianTagname) ExtractTagHistorize(string? tagConfig)
     {