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.Server/Security/Tls/SelfSignedCertificateProvider.cs

@@ -20,6 +20,10 @@ public sealed class SelfSignedCertificateProvider
     private readonly ILogger<SelfSignedCertificateProvider> _logger;
     private readonly TimeProvider _timeProvider;
 
+    /// <summary>Initializes a new instance of the <see cref="SelfSignedCertificateProvider"/> class.</summary>
+    /// <param name="options">TLS options controlling certificate generation and persistence.</param>
+    /// <param name="logger">Logger for certificate generation and load diagnostics.</param>
+    /// <param name="timeProvider">Time provider used for certificate validity and expiration checks.</param>
     public SelfSignedCertificateProvider(
         TlsOptions options,
         ILogger<SelfSignedCertificateProvider> logger,
@@ -31,6 +35,7 @@ public sealed class SelfSignedCertificateProvider
     }
 
     /// <summary>Creates a fresh in-memory ECDSA P-256 self-signed certificate.</summary>
+    /// <returns>The generated self-signed certificate.</returns>
     public X509Certificate2 GenerateCertificate()
     {
         using ECDsa key = ECDsa.Create(ECCurve.NamedCurves.nistP256);
@@ -89,6 +94,7 @@ public sealed class SelfSignedCertificateProvider
 
     /// <summary>Loads the persisted certificate, regenerating when missing,
     /// expired (and allowed), or unreadable.</summary>
+    /// <returns>The loaded or newly generated and persisted certificate.</returns>
     public X509Certificate2 LoadOrCreate()
     {
         string path = _options.SelfSignedCertPath;