feat(遊戲化): 新增大廳、附身、時間流、後日談進度等遊戲化系統功能

新增角色大廳（lobby）邀約與通話、附身（possession）、時鐘（clock）抽象、
時間流與睡眠負債、後日談進度、行為選擇與旁觀反應等模組，並補齊對應冒煙
測試（R~V）與單元測試；同步調整 web/mobile 對應頁面與元件。

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/api/src/romance/romance-eligibility.service.ts

@@ -1,6 +1,7 @@
 import { Injectable } from "@nestjs/common";
 import { PrismaService } from "../prisma/prisma.service.js";
 import { AgeDeterminationService } from "./age-determination.service.js";
+import { isOutsideSoloRoom } from "./room-context-guard.js";
 
 export interface RomanceEligibility {
   romanceAxisEligible: boolean; // 戀愛軸是否可啟動（含後日談自然成年者）
@@ -28,15 +29,20 @@ export class RomanceEligibilityService {
     return { romanceAxisEligible: currentAdult, adultModeEligible: canonAdult, isEpilogueAdult };
   }
 
-  async checkAdultContentAllowed(characterId: string, userId: string): Promise<AdultContentCheckResult> {
-    const result = await this.evaluate(characterId, userId);
+  async checkAdultContentAllowed(characterId: string, userId: string, roomId?: string): Promise<AdultContentCheckResult> {
+    const result = await this.evaluate(characterId, userId, roomId);
     await this.prisma.client.adultContentAttemptLog.create({
       data: { characterId, userId, allowed: result.allowed, reason: result.reason },
     });
     return result;
   }
 
-  private async evaluate(characterId: string, userId: string): Promise<AdultContentCheckResult> {
+  private async evaluate(characterId: string, userId: string, roomId?: string): Promise<AdultContentCheckResult> {
+    // T42：房型已轉為 GROUP／LOBBY／SELF_CHAT 時，成人內容一律禁止——房型本身是硬邊界，
+    // 不受角色資格或使用者 opt-in 狀態影響，優先於下方其他判斷。
+    if (await isOutsideSoloRoom(this.prisma, roomId)) {
+      return { allowed: false, reason: "目前在多人房（GROUP／LOBBY／SELF_CHAT），成人內容僅限 1:1 房間" };
+    }
     const eligibility = await this.getEligibility(characterId);
     if (!eligibility.adultModeEligible) {
       return {