feat(missions): add 3 catalog entities (mission, achievement, BP monthly)

SVSim.Database/Models/AchievementCatalogEntry.cs

@@ -0,0 +1,23 @@
+using SVSim.Database.Common;
+
+namespace SVSim.Database.Models;
+
+/// <summary>
+/// One tier of an achievement. PK is composite (AchievementType, Level). Rows are seeded from
+/// <c>seeds/achievement-catalog.json</c>. The captured tier IS the max tier in our world —
+/// max_level on the wire is computed as MAX(Level) per AchievementType at /mission/info time.
+/// Inherits Id from BaseEntity but the Id is unused; PK is configured in DbContext.
+/// </summary>
+public class AchievementCatalogEntry
+{
+    public int AchievementType { get; set; }
+    public int Level { get; set; }
+    public string Name { get; set; } = "";
+    public int RequireNumber { get; set; }
+    public int RewardType { get; set; }
+    public long RewardDetailId { get; set; }
+    public int RewardNumber { get; set; }
+    public int OrderNum { get; set; }
+    public string? EventType { get; set; }
+    public int? EventArg { get; set; }
+}