feat: 添加 ORPC 类型安全 RPC 层集成指南

- 添加 ORPC 类型安全 RPC 层的完整集成指南，包括合约定义、处理器实现、路由注册及在组件中使用的方法。

AGENTS.md

@@ -11,6 +11,7 @@ This document provides comprehensive guidelines for AI coding agents working in
 - **Database**: PostgreSQL with Drizzle ORM
 - **State Management**: TanStack Query
 - **Routing**: TanStack Router (file-based)
+- **RPC**: ORPC (type-safe RPC with contract-first design)
 - **Build Tool**: Vite
 - **Linter/Formatter**: Biome
 
@@ -212,9 +213,19 @@ src/
 │   ├── schema/        # Drizzle schema definitions
 │   └── index.ts       # Database instance
 ├── lib/               # Utility functions
+├── orpc/              # ORPC (RPC layer)
+│   ├── contracts/     # Contract definitions (input/output schemas)
+│   ├── handlers/      # Server-side procedure implementations
+│   ├── middlewares/   # Middleware (e.g., DB provider)
+│   ├── contract.ts    # Contract aggregation
+│   ├── router.ts      # Router composition
+│   ├── server.ts      # Server instance
+│   ├── client.ts      # Isomorphic client
+│   └── types.ts       # Type utilities
 ├── routes/            # TanStack Router file-based routes
 │   ├── __root.tsx     # Root layout
-│   └── index.tsx      # Home page
+│   ├── index.tsx      # Home page
+│   └── api/rpc.$.ts   # ORPC HTTP endpoint
 ├── env.ts             # Environment variable validation
 ├── index.ts           # Application entry point
 ├── router.tsx         # Router configuration
@@ -261,7 +272,52 @@ const myServerFn = createServerFn({ method: 'POST' })
   })
 ```
 
+### Creating ORPC Procedures
+
+**Step 1: Define Contract** (`src/orpc/contracts/my-feature.ts`)
+```typescript
+import { oc } from '@orpc/contract'
+import { z } from 'zod'
+
+export const myContract = {
+  get: oc.input(z.object({ id: z.uuid() })).output(mySchema),
+  create: oc.input(createSchema).output(mySchema),
+}
+```
+
+**Step 2: Implement Handler** (`src/orpc/handlers/my-feature.ts`)
+```typescript
+import { os } from '@/orpc/server'
+import { dbProvider } from '@/orpc/middlewares'
+
+export const get = os.myFeature.get
+  .use(dbProvider)
+  .handler(async ({ context, input }) => {
+    const item = await context.db.query.myTable.findFirst(...)
+    return item
+  })
+```
+
+**Step 3: Register in Contract & Router**
+```typescript
+// src/orpc/contract.ts
+export const contract = {
+  myFeature: myContract,
+}
+
+// src/orpc/router.ts
+import * as myFeature from './handlers/my-feature'
+export const router = os.router({ myFeature })
+```
+
+**Step 4: Use in Component**
+```typescript
+import { orpc } from '@/orpc'
+const query = useSuspenseQuery(orpc.myFeature.get.queryOptions({ id }))
+const mutation = useMutation(orpc.myFeature.create.mutationOptions())
+```
+
 ---
 
-**Last Updated**: 2026-01-17
+**Last Updated**: 2026-01-18
 **Project Version**: Based on package.json dependencies