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.

tests/Core/ZB.MOM.WW.OtOpcUa.Configuration.Tests/DriverHostStatusTests.cs

@@ -16,6 +16,7 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.Tests;
 [Collection(nameof(SchemaComplianceCollection))]
 public sealed class DriverHostStatusTests(SchemaComplianceFixture fixture)
 {
+    /// <summary>Verifies that the composite key allows the same host across different nodes or drivers.</summary>
     [Fact]
     public async Task Composite_key_allows_same_host_across_different_nodes_or_drivers()
     {
@@ -56,6 +57,7 @@ public sealed class DriverHostStatusTests(SchemaComplianceFixture fixture)
         rows.ShouldContain(r => r.NodeId == "node-a" && r.DriverInstanceId == "modbus-plc1");
     }
 
+    /// <summary>Verifies that the upsert pattern updates existing records in place.</summary>
     [Fact]
     public async Task Upsert_pattern_for_same_key_updates_in_place()
     {
@@ -94,6 +96,7 @@ public sealed class DriverHostStatusTests(SchemaComplianceFixture fixture)
         (await ctx3.DriverHostStatuses.CountAsync(r => r.NodeId == "upsert-node")).ShouldBe(1);
     }
 
+    /// <summary>Verifies that the State enum is persisted as a string, not an integer.</summary>
     [Fact]
     public async Task Enum_persists_as_string_not_int()
     {