Refactor raid rotation to use priority-based selection

Replaced fragile index tracking with a fresh calculation system that selects the next raid based on priority rules (User Requests > Mystery Raids > Configured Raids). This eliminates index out of bounds errors that occurred when Mystery Raids were dynamically inserted into the rotation.

Author: hexbyt3

SysBot.Pokemon/Helpers/SVRaidBot.cs

@@ -2,7 +2,7 @@
 {
     public static class SVRaidBot
     {
-        public const string Version = "v8.7.3";
+        public const string Version = "v8.7.4";
         public const string Repo = "https://github.com/hexbyt3/SVRaidBot";
         public const string ConfigPath = "config.json";
     }