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/Gateway/Dashboard/DashboardGalaxySummaryProjectorTests.cs

@@ -130,6 +130,8 @@ public sealed class DashboardGalaxySummaryProjectorTests
     ///     Verifies that the cache status enum is faithfully mapped to the dashboard
     ///     status enum across every defined value.
     /// </summary>
+    /// <param name="cacheStatus">The Galaxy cache status to project.</param>
+    /// <param name="expected">The expected dashboard status for the given cache status.</param>
     [Theory]
     [InlineData(GalaxyCacheStatus.Healthy, DashboardGalaxyStatus.Healthy)]
     [InlineData(GalaxyCacheStatus.Stale, DashboardGalaxyStatus.Stale)]