types(guide): 🏷️ Update TypeScript guide data interfaces for game metadata validation

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

guide/engine/src/types/game-data.ts

@@ -275,8 +275,10 @@ export interface Government {
 export interface Era {
   id: string
   name: string
+  display_name: string
   description: string
-  trigger: { type: string }
+  trigger: { type: string; required_techs?: number; pillar?: string }
+  max_event_tier: number
   flavor_text: string
 }