docs(src): add missing XML docs and strip tracking-ID comments

Sweep of 203 source files resolving CommentChecker findings: add
<summary>/<param>/<returns>/<inheritdoc> where missing, and remove
resolved task/issue tracking markers (Tests-NNN, Worker-NNN, Server-NNN,
Task N) from code comments. Comment/doc-only — no logic changes.
Server+Tests build clean under TreatWarningsAsErrors.

src/ZB.MOM.WW.MxGateway.Tests/Contracts/ProtobufContractRoundTripTests.cs

@@ -347,8 +347,8 @@ public sealed class ProtobufContractRoundTripTests
     ///     by-name-specific payload case and instead reuses the
     ///     <c>acknowledge_alarm</c> (<see cref="AcknowledgeAlarmReplyPayload"/>)
     ///     case. A future change that adds a separate by-name reply case — or
-    ///     drops the reuse — breaks this test. See Contracts-002 and
-    ///     docs/AlarmClientDiscovery.md section 4.
+    ///     drops the reuse — breaks this test. See docs/AlarmClientDiscovery.md
+    ///     section 4.
     /// </summary>
     [Fact]
     public void MxCommandReply_AcknowledgeAlarmByName_ReusesAcknowledgeAlarmPayloadCase()
@@ -1015,8 +1015,6 @@ public sealed class ProtobufContractRoundTripTests
     ///     Verifies that a <see cref="WriteSecuredBulkCommand"/> round-trips,
     ///     pinning the credential-bearing entry shape
     ///     (<c>current_user_id</c>, <c>verifier_user_id</c>, <c>value</c>).
-    ///     See Contracts-011 for the credential-sensitivity comment on
-    ///     <c>WriteSecuredBulkEntry.value</c>.
     /// </summary>
     [Fact]
     public void WriteSecuredBulkCommand_RoundTripsCredentialBearingEntries()
@@ -1597,7 +1595,7 @@ public sealed class ProtobufContractRoundTripTests
     ///     <see cref="MxSparseArray"/> with at least one <see cref="MxSparseElement"/>
     ///     so a future renumber or type-narrowing is caught at the contract level.
     ///     Also verifies that an all-defaults <see cref="MxSparseArray"/> (no elements)
-    ///     is not a proto-level error. See Contracts-023.
+    ///     is not a proto-level error.
     /// </summary>
     [Fact]
     public void MxValue_RoundTripsSparseArrayValueAndPinsFieldNumbers()