docs: complete XML doc comments via fixdocs (2757 to 131 findings)

Add missing <returns>/<param>/<summary>/<typeparam> tags and clean up
misused inheritdoc across 481 files so the documented API surface is
complete. Documentation-only (zero code lines changed). The 131 remaining
findings are inheritdoc-style warnings deliberately left to preserve
hand-written implementation rationale (plan-decision notes, race-condition
explanations).

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Galaxy.Tests/GalaxyDriverApiKeyResolverTests.cs

@@ -130,13 +130,24 @@ public sealed class GalaxyDriverApiKeyResolverTests
         /// <summary>Gets the list of captured log entries with their levels and messages.</summary>
         public List<(LogLevel Level, string Message)> Entries { get; } = new();
 
-        /// <inheritdoc />
+        /// <summary>Begins a logging scope (returns null — no scope support in test logger).</summary>
+        /// <typeparam name="TState">The type of the state object.</typeparam>
+        /// <param name="state">The state object.</param>
+        /// <returns>Null — test logger has no scope support.</returns>
         public IDisposable? BeginScope<TState>(TState state) where TState : notnull => null;
 
-        /// <inheritdoc />
+        /// <summary>Returns true for all log levels so all messages are captured.</summary>
+        /// <param name="logLevel">The log level to check.</param>
+        /// <returns>Always true.</returns>
         public bool IsEnabled(LogLevel logLevel) => true;
 
-        /// <inheritdoc />
+        /// <summary>Captures the log message and level into the Entries list.</summary>
+        /// <typeparam name="TState">The type of the state object.</typeparam>
+        /// <param name="logLevel">The log level.</param>
+        /// <param name="eventId">The event ID.</param>
+        /// <param name="state">The state object.</param>
+        /// <param name="exception">The exception, if any.</param>
+        /// <param name="formatter">The formatter function.</param>
         public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter)
             => Entries.Add((logLevel, formatter(state, exception)));
     }