MMO Skill Tree Mastery Pack

Full 9-language localization of every display string (track titles, node names + descriptions including the shared tier names, quests, achievements, currency names, shop offer). Fixes the Mastery Infusion offer never actually appearing in the shop (1.0.1 shipped it in the wrong content folder with a stale Control key). Reward lines drop their baked English names; the plugin renders localized amounts instead. Adds a Mastery Infusion shop offer (convert Bounty Tokens into a Mastery Point), active when the Bounty Pack and plugin 1.3.0+ are present. Core mastery content unchanged.