Fix MariaDB dbimport: utf8mb4 collation and dbimport.conf

Use utf8mb4_unicode_ci in base SQL (MariaDB lacks utf8mb4_0900_ai_ci).
Add Updates.ExceptionShutdownDelay to dbimport.conf.dist to match
DBUpdater expectations.

data/sql/base/db_characters/world_state.sql

@@ -24,7 +24,7 @@ CREATE TABLE `world_state` (
   `Id` int unsigned NOT NULL COMMENT 'Internal save ID',
   `Data` longtext,
   PRIMARY KEY (`Id`)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT='WorldState save system';
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='WorldState save system';
 /*!40101 SET character_set_client = @saved_cs_client */;
 
 --

data/sql/base/db_world/player_shapeshift_model.sql

@@ -27,7 +27,7 @@ CREATE TABLE `player_shapeshift_model` (
   `GenderID` tinyint unsigned NOT NULL,
   `ModelID` int unsigned NOT NULL,
   PRIMARY KEY (`ShapeshiftID`,`RaceID`,`CustomizationID`,`GenderID`)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci PACK_KEYS=0;
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci PACK_KEYS=0;
 /*!40101 SET character_set_client = @saved_cs_client */;
 
 --

data/sql/base/db_world/player_totem_model.sql

@@ -25,7 +25,7 @@ CREATE TABLE `player_totem_model` (
   `RaceID` tinyint unsigned NOT NULL,
   `ModelID` int unsigned NOT NULL,
   PRIMARY KEY (`TotemID`,`RaceID`)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci PACK_KEYS=0;
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci PACK_KEYS=0;
 /*!40101 SET character_set_client = @saved_cs_client */;
 
 --

src/tools/dbimport/dbimport.conf.dist

@@ -215,6 +215,14 @@ Updates.AllowRehash = 1
 #                    -1 - (Enabled - unlimited)
 
 Updates.CleanDeadRefMaxCount = 3
+
+#
+#    Updates.ExceptionShutdownDelay
+#        Description: Time (in milliseconds) to wait before shutting down after a fatal exception (e.g. failed SQL update).
+#        Default:     10000 - 10 seconds
+#                     0     - Disabled (immediate shutdown)
+
+Updates.ExceptionShutdownDelay = 10000
 ###################################################################################################
 
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