refactor: 重构待办事项合约导入与导出方式

- 更新导入方式，将 todoContract 的导入改为命名空间导入并直接引用整个模块。
- 重构待办事项合约，将各操作方法从对象结构中提取为独立导出的常量。

src/orpc/contract.ts

@@ -1,5 +1,5 @@
-import { todoContract } from './contracts/todo'
+import * as todo from './contracts/todo'
 
 export const contract = {
-  todo: todoContract,
+  todo,
 }

src/orpc/contracts/todo.ts

@@ -21,25 +21,23 @@ const updateSchema = createUpdateSchema(todoTable).omit({
   updatedAt: true,
 })
 
-export const todoContract = {
+export const list = oc.input(z.void()).output(z.array(selectSchema))
-  list: oc.input(z.void()).output(z.array(selectSchema)),
 
-  create: oc.input(insertSchema).output(selectSchema),
+export const create = oc.input(insertSchema).output(selectSchema)
 
-  update: oc
+export const update = oc
   .input(
     z.object({
       id: z.uuid(),
       data: updateSchema,
     }),
   )
-    .output(selectSchema),
+  .output(selectSchema)
 
-  remove: oc
+export const remove = oc
   .input(
     z.object({
       id: z.uuid(),
     }),
   )
-    .output(z.void()),
+  .output(z.void())
-}