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/Core/ZB.MOM.WW.OtOpcUa.Configuration.Tests/LdapGroupRoleMappingServiceTests.cs

@@ -34,6 +34,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
         };
 
     /// <summary>Verifies that Create sets Id and CreatedAtUtc.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Create_SetsId_AndCreatedAtUtc()
     {
@@ -47,6 +48,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that Create rejects empty LDAP group.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Create_Rejects_EmptyLdapGroup()
     {
@@ -58,6 +60,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that Create rejects system-wide mapping with ClusterId.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Create_Rejects_SystemWide_With_ClusterId()
     {
@@ -69,6 +72,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that Create rejects non-system-wide mapping without ClusterId.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Create_Rejects_NonSystemWide_WithoutClusterId()
     {
@@ -80,6 +84,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that GetByGroups returns only matching grants.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task GetByGroups_Returns_MatchingGrants_Only()
     {
@@ -96,6 +101,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that GetByGroups returns empty when input is empty.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task GetByGroups_Empty_Input_ReturnsEmpty()
     {
@@ -108,6 +114,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that ListAll orders results by group then cluster.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task ListAll_Orders_ByGroupThenCluster()
     {
@@ -125,6 +132,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that Delete removes the matching row.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Delete_Removes_Matching_Row()
     {
@@ -138,6 +146,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that Delete with unknown Id is a no-op.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task Delete_Unknown_Id_IsNoOp()
     {
@@ -148,6 +157,7 @@ public sealed class LdapGroupRoleMappingServiceTests : IDisposable
     }
 
     /// <summary>Verifies that a system-wide row (IsSystemWide=true, ClusterId=null) appears in both ListAllAsync and GetByGroupsAsync.</summary>
+    /// <returns>A task that represents the asynchronous test operation.</returns>
     [Fact]
     public async Task SystemWide_Row_AppearsIn_ListAll_And_GetByGroups()
     {