docs: backfill XML documentation across 756 files

Adds <summary>, <param>, <typeparam>, and <inheritdoc/> tags to public
members surfaced by commentchecker — resolves 5,847 of 5,869 issues
(99.6%) across three /fixdocs passes.

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/LocalCache/GenerationSealedCache.cs

@@ -31,6 +31,8 @@ public sealed class GenerationSealedCache
     /// <summary>Root directory for all clusters' sealed caches.</summary>
     public string CacheRoot => _cacheRoot;
 
+    /// <summary>Initializes a new instance of the GenerationSealedCache class.</summary>
+    /// <param name="cacheRoot">The root directory for the cache.</param>
     public GenerationSealedCache(string cacheRoot)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(cacheRoot);
@@ -43,6 +45,9 @@ public sealed class GenerationSealedCache
     ///     mark the file read-only, then atomically publish the <c>CURRENT</c> pointer. Existing
     ///     sealed files for prior generations are preserved (prune separately).
     /// </summary>
+    /// <param name="snapshot">The generation snapshot to seal.</param>
+    /// <param name="ct">The cancellation token.</param>
+    /// <returns>A task representing the asynchronous operation.</returns>
     public async Task SealAsync(GenerationSnapshot snapshot, CancellationToken ct = default)
     {
         ArgumentNullException.ThrowIfNull(snapshot);
@@ -88,6 +93,9 @@ public sealed class GenerationSealedCache
     ///     (first-boot-no-snapshot case) or when the sealed file is corrupt. Never silently
     ///     falls back to a prior generation.
     /// </summary>
+    /// <param name="clusterId">The cluster ID to read the snapshot for.</param>
+    /// <param name="ct">The cancellation token.</param>
+    /// <returns>A task representing the asynchronous operation containing the generation snapshot.</returns>
     public Task<GenerationSnapshot> ReadCurrentAsync(string clusterId, CancellationToken ct = default)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(clusterId);
@@ -135,6 +143,8 @@ public sealed class GenerationSealedCache
     }
 
     /// <summary>Return the generation id the <c>CURRENT</c> pointer points at, or null if no pointer exists.</summary>
+    /// <param name="clusterId">The cluster ID to get the current generation ID for.</param>
+    /// <returns>The generation ID, or null if no pointer exists.</returns>
     public long? TryGetCurrentGenerationId(string clusterId)
     {
         ArgumentException.ThrowIfNullOrWhiteSpace(clusterId);
@@ -165,6 +175,11 @@ public sealed class GenerationSealedCache
 /// <summary>Sealed cache is unreachable — caller must fail closed.</summary>
 public sealed class GenerationCacheUnavailableException : Exception
 {
+    /// <summary>Initializes a new instance of the GenerationCacheUnavailableException class.</summary>
+    /// <param name="message">The error message.</param>
     public GenerationCacheUnavailableException(string message) : base(message) { }
+    /// <summary>Initializes a new instance of the GenerationCacheUnavailableException class with an inner exception.</summary>
+    /// <param name="message">The error message.</param>
+    /// <param name="inner">The inner exception.</param>
     public GenerationCacheUnavailableException(string message, Exception inner) : base(message, inner) { }
 }

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/LocalCache/GenerationSnapshot.cs

@@ -7,9 +7,14 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.LocalCache;
 /// </summary>
 public sealed class GenerationSnapshot
 {
+    /// <summary>Gets or sets the auto-generated LiteDB ID.</summary>
     public int Id { get; set; } // LiteDB auto-ID
+    /// <summary>Gets or sets the cluster identifier.</summary>
     public required string ClusterId { get; set; }
+    /// <summary>Gets or sets the generation identifier.</summary>
     public required long GenerationId { get; set; }
+    /// <summary>Gets or sets the time this snapshot was cached.</summary>
     public required DateTime CachedAt { get; set; }
+    /// <summary>Gets or sets the JSON-serialized payload content.</summary>
     public required string PayloadJson { get; set; }
 }

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/LocalCache/ILocalConfigCache.cs

@@ -13,7 +13,18 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.LocalCache;
 /// </remarks>
 public interface ILocalConfigCache
 {
+    /// <summary>Retrieves the most recent generation snapshot for the specified cluster.</summary>
+    /// <param name="clusterId">The cluster identifier.</param>
+    /// <param name="ct">The cancellation token.</param>
+    /// <returns>The most recent generation snapshot, or null if none exists.</returns>
     Task<GenerationSnapshot?> GetMostRecentAsync(string clusterId, CancellationToken ct = default);
+    /// <summary>Stores a generation snapshot in the local cache.</summary>
+    /// <param name="snapshot">The generation snapshot to store.</param>
+    /// <param name="ct">The cancellation token.</param>
     Task PutAsync(GenerationSnapshot snapshot, CancellationToken ct = default);
+    /// <summary>Removes old generations, keeping only the most recent N.</summary>
+    /// <param name="clusterId">The cluster identifier.</param>
+    /// <param name="keepLatest">The number of latest generations to keep.</param>
+    /// <param name="ct">The cancellation token.</param>
     Task PruneOldGenerationsAsync(string clusterId, int keepLatest = 10, CancellationToken ct = default);
 }

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/LocalCache/LiteDbConfigCache.cs

@@ -20,6 +20,8 @@ public sealed class LiteDbConfigCache : ILocalConfigCache, IDisposable
     // page-level write, not the find-then-insert window.
     private readonly SemaphoreSlim _writeGate = new(initialCount: 1, maxCount: 1);
 
+    /// <summary>Initializes a new instance of the <see cref="LiteDbConfigCache"/> class.</summary>
+    /// <param name="dbPath">Path to the LiteDB database file.</param>
     public LiteDbConfigCache(string dbPath)
     {
         // LiteDB can be tolerant of header-only corruption at construction time (it may overwrite
@@ -43,6 +45,9 @@ public sealed class LiteDbConfigCache : ILocalConfigCache, IDisposable
         }
     }
 
+    /// <summary>Gets the most recent snapshot for the specified cluster.</summary>
+    /// <param name="clusterId">The cluster ID.</param>
+    /// <param name="ct">Cancellation token.</param>
     public Task<GenerationSnapshot?> GetMostRecentAsync(string clusterId, CancellationToken ct = default)
     {
         ct.ThrowIfCancellationRequested();
@@ -53,6 +58,9 @@ public sealed class LiteDbConfigCache : ILocalConfigCache, IDisposable
         return Task.FromResult<GenerationSnapshot?>(snapshot);
     }
 
+    /// <summary>Stores a snapshot in the cache.</summary>
+    /// <param name="snapshot">The snapshot to store.</param>
+    /// <param name="ct">Cancellation token.</param>
     public async Task PutAsync(GenerationSnapshot snapshot, CancellationToken ct = default)
     {
         ct.ThrowIfCancellationRequested();
@@ -81,6 +89,10 @@ public sealed class LiteDbConfigCache : ILocalConfigCache, IDisposable
         }
     }
 
+    /// <summary>Removes old generation snapshots, keeping only the latest ones.</summary>
+    /// <param name="clusterId">The cluster ID.</param>
+    /// <param name="keepLatest">Number of latest generations to keep.</param>
+    /// <param name="ct">Cancellation token.</param>
     public Task PruneOldGenerationsAsync(string clusterId, int keepLatest = 10, CancellationToken ct = default)
     {
         ct.ThrowIfCancellationRequested();
@@ -97,6 +109,7 @@ public sealed class LiteDbConfigCache : ILocalConfigCache, IDisposable
         return Task.CompletedTask;
     }
 
+    /// <summary>Releases all resources used by the cache.</summary>
     public void Dispose()
     {
         _writeGate.Dispose();

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/LocalCache/ResilientConfigReader.cs

@@ -27,6 +27,12 @@ public sealed class ResilientConfigReader
     private readonly ResiliencePipeline _pipeline;
     private readonly ILogger<ResilientConfigReader> _logger;
 
+    /// <summary>Initializes a resilient config reader with the given cache and options.</summary>
+    /// <param name="cache">The sealed cache for fallback.</param>
+    /// <param name="staleFlag">The stale config flag to manage.</param>
+    /// <param name="logger">The logger instance.</param>
+    /// <param name="timeout">The timeout for central fetch (default 2s).</param>
+    /// <param name="retryCount">The number of retries (default 3).</param>
     public ResilientConfigReader(
         GenerationSealedCache cache,
         StaleConfigFlag staleFlag,
@@ -71,6 +77,9 @@ public sealed class ResilientConfigReader
         @"(?ix)\b(Password|Pwd|User\s*Id|Uid|AccessToken|Authorization|Api[-_]?Key)\s*=\s*[^;,)\s]*",
         RegexOptions.Compiled);
 
+    /// <summary>Redacts sensitive credential information from a message.</summary>
+    /// <param name="message">The message to scrub.</param>
+    /// <returns>The message with redacted credentials.</returns>
     internal static string ScrubSecrets(string? message)
     {
         if (string.IsNullOrEmpty(message)) return message ?? string.Empty;
@@ -80,10 +89,15 @@ public sealed class ResilientConfigReader
     }
 
     /// <summary>
-    ///     Execute <paramref name="centralFetch"/> through the resilience pipeline. On full failure
-    ///     (post-retry), reads the sealed cache for <paramref name="clusterId"/> and passes the
-    ///     snapshot to <paramref name="fromSnapshot"/> to extract the requested shape.
+    ///     Executes a central fetch through the resilience pipeline. On full failure
+    ///     (post-retry), reads the sealed cache and extracts the requested shape.
     /// </summary>
+    /// <typeparam name="T">The type of configuration to read.</typeparam>
+    /// <param name="clusterId">The cluster ID to fetch for.</param>
+    /// <param name="centralFetch">Function to fetch from central DB.</param>
+    /// <param name="fromSnapshot">Function to extract the config from a snapshot.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The configuration of type T.</returns>
     public async ValueTask<T> ReadAsync<T>(
         string clusterId,
         Func<CancellationToken, ValueTask<T>> centralFetch,