Core/DataStores: implement PlayerCondition.dbc

* additionally implemented a DB table for custom entries as many of these conditions are strictly server side
* use server side conditions for Stormwind's faction vendor as example usage

sql/updates/world/4.3.4/2023_07_17_00_world.sql

@@ -0,0 +1,13 @@
+DROP TABLE IF EXISTS `playercondition_dbc`;
+CREATE TABLE `playercondition_dbc` (  
+  `ID` INT UNSIGNED NOT NULL,
+  `FailureDescription` VARCHAR(100) NOT NULL,
+  PRIMARY KEY (`ID`) 
+);
+
+INSERT INTO `playercondition_dbc` (`ID`, `FailureDescription`) VALUES
+(12251, 'Serverside/Non-DB2: Requires Stormwind - Revered'),
+(12252, 'Serverside/Non-DB2: Requires Stormwind - Exalted');
+
+UPDATE `npc_vendor` SET `PlayerConditionID`= 12252 WHERE `item` IN (64901, 64902, 64903);
+UPDATE `npc_vendor` SET `PlayerConditionID`= 12251 WHERE `item`= 67531;