docs(zh-CN): sync Chinese docs with latest upstream changes

docs/zh-CN/rules/rust/patterns.md

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+---
+paths:
+  - "**/*.rs"
+---
+
+# Rust 设计模式
+
+> 本文档在 [common/patterns.md](../common/patterns.md) 的基础上，补充了 Rust 特有的内容。
+
+## 基于 Trait 的 Repository 模式
+
+将数据访问封装在 trait 之后：
+
+```rust
+pub trait OrderRepository: Send + Sync {
+    fn find_by_id(&self, id: u64) -> Result<Option<Order>, StorageError>;
+    fn find_all(&self) -> Result<Vec<Order>, StorageError>;
+    fn save(&self, order: &Order) -> Result<Order, StorageError>;
+    fn delete(&self, id: u64) -> Result<(), StorageError>;
+}
+```
+
+具体的实现负责处理存储细节（如 Postgres、SQLite，或用于测试的内存存储）。
+
+## 服务层
+
+业务逻辑位于服务结构体中；通过构造函数注入依赖：
+
+```rust
+pub struct OrderService {
+    repo: Box<dyn OrderRepository>,
+    payment: Box<dyn PaymentGateway>,
+}
+
+impl OrderService {
+    pub fn new(repo: Box<dyn OrderRepository>, payment: Box<dyn PaymentGateway>) -> Self {
+        Self { repo, payment }
+    }
+
+    pub fn place_order(&self, request: CreateOrderRequest) -> anyhow::Result<OrderSummary> {
+        let order = Order::from(request);
+        self.payment.charge(order.total())?;
+        let saved = self.repo.save(&order)?;
+        Ok(OrderSummary::from(saved))
+    }
+}
+```
+
+## 为类型安全使用 Newtype 模式
+
+使用不同的包装类型防止参数混淆：
+
+```rust
+struct UserId(u64);
+struct OrderId(u64);
+
+fn get_order(user: UserId, order: OrderId) -> anyhow::Result<Order> {
+    // Can't accidentally swap user and order IDs at call sites
+    todo!()
+}
+```
+
+## 枚举状态机
+
+将状态建模为枚举 —— 使非法状态无法表示：
+
+```rust
+enum ConnectionState {
+    Disconnected,
+    Connecting { attempt: u32 },
+    Connected { session_id: String },
+    Failed { reason: String, retries: u32 },
+}
+
+fn handle(state: &ConnectionState) {
+    match state {
+        ConnectionState::Disconnected => connect(),
+        ConnectionState::Connecting { attempt } if *attempt > 3 => abort(),
+        ConnectionState::Connecting { .. } => wait(),
+        ConnectionState::Connected { session_id } => use_session(session_id),
+        ConnectionState::Failed { retries, .. } if *retries < 5 => retry(),
+        ConnectionState::Failed { reason, .. } => log_failure(reason),
+    }
+}
+```
+
+始终进行穷尽匹配 —— 对于业务关键的枚举，不要使用通配符 `_`。
+
+## 建造者模式
+
+适用于具有多个可选参数的结构体：
+
+```rust
+pub struct ServerConfig {
+    host: String,
+    port: u16,
+    max_connections: usize,
+}
+
+impl ServerConfig {
+    pub fn builder(host: impl Into<String>, port: u16) -> ServerConfigBuilder {
+        ServerConfigBuilder {
+            host: host.into(),
+            port,
+            max_connections: 100,
+        }
+    }
+}
+
+pub struct ServerConfigBuilder {
+    host: String,
+    port: u16,
+    max_connections: usize,
+}
+
+impl ServerConfigBuilder {
+    pub fn max_connections(mut self, n: usize) -> Self {
+        self.max_connections = n;
+        self
+    }
+
+    pub fn build(self) -> ServerConfig {
+        ServerConfig {
+            host: self.host,
+            port: self.port,
+            max_connections: self.max_connections,
+        }
+    }
+}
+```
+
+## 密封 Trait 以控制扩展性
+
+使用私有模块来密封一个 trait，防止外部实现：
+
+```rust
+mod private {
+    pub trait Sealed {}
+}
+
+pub trait Format: private::Sealed {
+    fn encode(&self, data: &[u8]) -> Vec<u8>;
+}
+
+pub struct Json;
+impl private::Sealed for Json {}
+impl Format for Json {
+    fn encode(&self, data: &[u8]) -> Vec<u8> { todo!() }
+}
+```
+
+## API 响应包装器
+
+使用泛型枚举实现一致的 API 响应：
+
+```rust
+#[derive(Debug, serde::Serialize)]
+#[serde(tag = "status")]
+pub enum ApiResponse<T: serde::Serialize> {
+    #[serde(rename = "ok")]
+    Ok { data: T },
+    #[serde(rename = "error")]
+    Error { message: String },
+}
+```
+
+## 参考资料
+
+参见技能：`rust-patterns`，其中包含全面的模式，涵盖所有权、trait、泛型、并发和异步。