Add research queue: queue multiple projects, auto-promote on completion, RP refund on dequeue

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/shared/src/types/research.ts

@@ -3,6 +3,7 @@ import type { Era } from './gameState';
 export interface ResearchState {
   completedResearch: string[];
   activeResearch: ActiveResearch | null;
+  researchQueue: string[];
   researchPoints: number;
 }
 
@@ -41,5 +42,6 @@ export interface ResearchEffect {
 export const INITIAL_RESEARCH: ResearchState = {
   completedResearch: [],
   activeResearch: null,
+  researchQueue: [],
   researchPoints: 0,
 };