refactor: drop unused DailyLoginBonuses table + importer

The captured shape ({"1":[], "3":[], "4":[]}) is the empty-period
wire echo; the client parser (LoadDetail.cs:553) only reads normal/total/
campaign. Table, entity, seed, and importer were never wired to a code path.

Replaced by config-section catalog + service in the follow-up commits.

SVSim.Bootstrap/Models/Seed/DailyLoginBonusSeed.cs

@@ -1,11 +0,0 @@
-using System.Text.Json;
-using System.Text.Json.Serialization;
-
-namespace SVSim.Bootstrap.Models.Seed;
-
-/// <summary>Mirrors <c>seeds/daily-login-bonus.json</c>. <c>bonus_data</c> preserved verbatim.</summary>
-public sealed class DailyLoginBonusSeed
-{
-    [JsonPropertyName("id")] public int Id { get; set; }
-    [JsonPropertyName("bonus_data")] public JsonElement BonusData { get; set; }
-}