feat: 完成 B 群組 — 資料層與核心領域模型

- 導入 Prisma 7.9.1 + SQLite（better-sqlite3 driver adapter），prisma.config.ts 管理連線設定
- 完整資料模型：User／Work／Character／CharacterAlias／EpisodicMemory／SemanticMemory／
  ProceduralRule／EmotionState／Relationship／SentimentLedgerEntry
- packages/db：Prisma Client 存取層（ESM，因 Prisma 7 產出的 generated client 僅支援 ESM）
- apps/api 隨之改為 ESM 以相容 packages/db
- packages/shared：新增角色／記憶／情緒／關係共用型別，api 與 web 皆從此匯入
- prisma/seed.ts：建立測試使用者與元氣型測試角色，含完整關係帳本與記憶種子資料
- apps/api：新增 GET /characters
- scripts/smoke/B.mjs：驗證資料表齊全、API 讀出種子角色、關係與記憶可寫入讀出
- 保留 Prisma 官方隨 CLI 附的 agent skill 文件（.agents/skills 等），供後續群組查閱

npm run restart && npm run smoke -- B 皆通過（B-V），A 群組冒煙測試無回歸。

.agents/skills/prisma-database-setup/references/postgresql.md

@@ -0,0 +1,92 @@
+# PostgreSQL Setup
+
+Configure Prisma with PostgreSQL.
+
+## Prerequisites
+
+- PostgreSQL database (local or cloud)
+- Connection string
+
+## 1. Schema Configuration
+
+In `prisma/schema.prisma`:
+
+```prisma
+datasource db {
+  provider = "postgresql"
+}
+
+generator client {
+  provider = "prisma-client"
+  output   = "../generated"
+}
+```
+
+## 2. Config Configuration
+
+In `prisma.config.ts`:
+
+```typescript
+import { defineConfig, env } from 'prisma/config'
+
+export default defineConfig({
+  schema: 'prisma/schema.prisma',
+  datasource: {
+    url: env('DATABASE_URL'),
+  },
+})
+```
+
+## 3. Environment Variable
+
+In `.env`:
+
+```env
+DATABASE_URL="postgresql://user:password@localhost:5432/mydb?schema=public"
+```
+
+### Connection String Format
+
+```
+postgresql://USER:PASSWORD@HOST:PORT/DATABASE?schema=SCHEMA
+```
+
+- **USER**: Database user
+- **PASSWORD**: Password (URL encoded if special chars)
+- **HOST**: Hostname (localhost, IP, or domain)
+- **PORT**: Port (default 5432)
+- **DATABASE**: Database name
+- **SCHEMA**: Schema name (default `public`)
+
+## Driver Adapter
+
+Use a driver adapter for the standard SQL workflow.
+
+1. Install adapter and driver:
+   ```bash
+   npm install @prisma/adapter-pg pg
+   ```
+
+2. Instantiate Prisma Client with the adapter:
+   ```typescript
+   import 'dotenv/config'
+   import { PrismaClient } from '../generated/client'
+   import { PrismaPg } from '@prisma/adapter-pg'
+
+   const adapter = new PrismaPg({ connectionString: process.env.DATABASE_URL })
+   const prisma = new PrismaClient({ adapter })
+   ```
+
+## Common Issues
+
+### "Can't reach database server"
+- Check host and port
+- Check firewall settings
+- Ensure database is running
+
+### "Authentication failed"
+- Check user/password
+- Special characters in password must be URL-encoded
+
+### "Schema does not exist"
+- Ensure `?schema=public` (or your schema) is in the URL