docs(xmldoc): fill missing XML docs + strip tracking-ID comments across src

Adds <summary>/<param>/<returns>/<inheritdoc> where missing and removes
project bookkeeping IDs (task/tracking refs) from shipped code comments,
so the docs read cleanly and CommentChecker is quiet except for known
false positives (PLC/protocol terms, event/IEqualityComparer inheritdoc).
Doc/comment-only; no logic changed; solution builds clean.

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ExternalIdReservation.cs

@@ -3,7 +3,7 @@ using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
 namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
 
 /// <summary>
-///     Fleet-wide rollback-safe reservation of ZTag and SAPID. Per decision #124 — NOT generation-versioned.
+///     Fleet-wide rollback-safe reservation of ZTag and SAPID. NOT generation-versioned.
 ///     Exists outside generation flow specifically because old generations and disabled equipment can
 ///     still hold the same external IDs; per-generation uniqueness indexes fail under rollback/re-enable.
 /// </summary>