Core/Creatures: implement overriding static flags by spawnId and difficulty

sql/updates/world/4.3.4/2025_03_11_02_world.sql

@@ -0,0 +1,11 @@
+DROP TABLE IF EXISTS `creature_static_flags_override`;
+CREATE TABLE `creature_static_flags_override` (  
+  `SpawnId` INT UNSIGNED NOT NULL,
+  `DifficultyId` TINYINT UNSIGNED NOT NULL DEFAULT 0,
+  `StaticFlags1` INT UNSIGNED,
+  `StaticFlags2` INT UNSIGNED,
+  `StaticFlags3` INT UNSIGNED,
+  `StaticFlags4` INT UNSIGNED,
+  `StaticFlags5` INT UNSIGNED,
+  PRIMARY KEY (`SpawnId`, `DifficultyId`) 
+);