Add init link.

API/ROLAC.API/Entities/UserInvitation.cs

@@ -0,0 +1,35 @@
+namespace ROLAC.API.Entities;
+
+/// <summary>
+/// A single-use, expiring invitation that lets a member set their own password and log in for
+/// the first time — without an admin-generated temporary password. The raw token is e-mailed /
+/// copied to the member; only its SHA-256 hash is stored here (same scheme as RefreshToken).
+/// </summary>
+public class UserInvitation
+{
+    public int Id { get; set; }
+
+    public string UserId { get; set; } = null!;
+    public AppUser User { get; set; } = null!;
+
+    /// <summary>SHA-256 hex of the raw invitation token. Never store raw tokens.</summary>
+    public string TokenHash { get; set; } = null!;
+
+    public DateTime ExpiresAt { get; set; }
+    public DateTime CreatedAt { get; set; }
+
+    /// <summary>Id of the admin who generated the link.</summary>
+    public string CreatedBy { get; set; } = null!;
+
+    /// <summary>Set when the member consumes the link to set their password (single-use).</summary>
+    public DateTime? UsedAt { get; set; }
+
+    /// <summary>Set when superseded by a newer invitation for the same user (re-issue).</summary>
+    public DateTime? RevokedAt { get; set; }
+
+    // Computed helpers — NOT mapped to DB columns (ignored in OnModelCreating)
+    public bool IsExpired => DateTime.UtcNow >= ExpiresAt;
+    public bool IsUsed    => UsedAt.HasValue;
+    public bool IsRevoked => RevokedAt.HasValue;
+    public bool IsActive  => !IsUsed && !IsRevoked && !IsExpired;
+}