add xmldoc comments

web/backend/Service/Service.Auth/ILoginService.cs

@@ -2,12 +2,28 @@ using Domain.Entities;
 
 namespace Service.Auth;
 
+/// <summary>
+/// Represents the result of a successful login attempt.
+/// </summary>
+/// <param name="UserAccount">The authenticated user's account.</param>
+/// <param name="RefreshToken">The issued refresh token.</param>
+/// <param name="AccessToken">The issued access token.</param>
 public record LoginServiceReturn(
     UserAccount UserAccount,
     string RefreshToken,
     string AccessToken
 );
+
+/// <summary>
+/// Defines the operation for authenticating a user with a username and password.
+/// </summary>
 public interface ILoginService
 {
+    /// <summary>
+    /// Authenticates a user using their username and password and issues new tokens.
+    /// </summary>
+    /// <param name="username">The username of the account to authenticate.</param>
+    /// <param name="password">The plain-text password to verify against the stored credential.</param>
+    /// <returns>A <see cref="LoginServiceReturn"/> containing the authenticated user and issued tokens.</returns>
     Task<LoginServiceReturn> LoginAsync(string username, string password);
 }