docs: add bilingual README with language switcher

- Update README.md to English version with language navigation
- Add README.zh-CN.md for Simplified Chinese
- Add language switcher links in both files

README.md

@@ -1,41 +1,47 @@
+<div align="center">
+
+[English](README.md) | [简体中文](README.zh-CN.md)
+
+</div>
+
 # PaddedCell
 
-OpenClaw 插件：安全密码管理 + 安全执行 + 安全重启
+OpenClaw plugin for secure password management, safe command execution, and coordinated agent restart.
 
-## 功能模块
+## Features
 
-### 1. pass_mgr - 密码管理二进制 (Go)
+### 1. pass_mgr - Password Manager Binary (Go)
 
-使用 AES-256-GCM 加密，每个 agent 基于公私钥进行加/解密。
+AES-256-GCM encryption, per-agent key-based encryption/decryption.
 
 ```bash
-# 初始化
+# Initialize
 pass_mgr admin init [--key-path <path>]
 
-# 获取密码
+# Get password
 pass_mgr get <key> [--username]
 
-# 生成密码 (agent 可用)
+# Generate password (agent can use)
 pass_mgr generate <key> [--username <user>]
 
-# 设置密码 (仅人类)
+# Set password (human only)
 pass_mgr set <key> <password> [--username <user>]
 
-# 删除密码
+# Delete password
 pass_mgr unset <key>
 
-# 轮换密码
+# Rotate password
 pass_mgr rotate <key>
 ```
 
-**安全特性：**
-- Agent 无法执行 `set` 操作（通过环境变量检测）
-- 未初始化前所有操作报错
-- Admin 密码泄露检测（监控 message/tool calling）
+**Security Features:**
+- Agents cannot execute `set` (detected via environment variables)
+- All operations fail before initialization
+- Admin password leak detection (monitors messages/tool calls)
 
-### 2. pcexec - 安全执行工具 (TypeScript)
+### 2. pcexec - Safe Execution Tool (TypeScript)
 
-与 OpenClaw 原生 exec 接口一致，自动处理 pass_mgr get 并脱敏输出。
+Compatible with OpenClaw native exec interface, automatically handles `pass_mgr get` and sanitizes output.
 
 ```typescript
 import { pcexec } from 'pcexec';
@@ -44,47 +50,47 @@ const result = await pcexec('echo $(pass_mgr get mypassword)', {
   cwd: '/workspace',
   timeout: 30000,
 });
-// result.stdout 中密码会被替换为 ######
+// Passwords in result.stdout will be replaced with ######
 ```
 
-### 3. safe-restart - 安全重启模块 (TypeScript)
+### 3. safe-restart - Safe Restart Module (TypeScript)
 
-提供 agent 状态管理和协调重启。
+Provides agent state management and coordinated restart.
 
-**Agent 状态：**
-- `idle` - 空闲
-- `busy` - 处理消息中
-- `focus` - 专注模式（工作流）
-- `freeze` - 冻结（不接受新消息）
-- `pre-freeze` - 准备冻结
-- `pre-freeze-focus` - 准备冻结（专注模式）
+**Agent States:**
+- `idle` - Idle
+- `busy` - Processing messages
+- `focus` - Focus mode (workflow)
+- `freeze` - Frozen (not accepting new messages)
+- `pre-freeze` - Preparing to freeze
+- `pre-freeze-focus` - Preparing to freeze (focus mode)
 
-**API：**
-- `POST /query-restart` - 查询重启就绪状态
-- `POST /restart-result` - 报告重启结果
-- `GET /status` - 获取所有状态
+**APIs:**
+- `POST /query-restart` - Query restart readiness
+- `POST /restart-result` - Report restart result
+- `GET /status` - Get all statuses
 
-**Slash 命令：**
+**Slash Commands:**
 ```
 /padded-cell-ctrl status
 /padded-cell-ctrl enable pass-mgr|safe-restart
 /padded-cell-ctrl disable pass-mgr|safe-restart
 ```
 
-## 目录结构
+## Project Structure
 
 ```
 PaddedCell/
-├── pass_mgr/           # Go 密码管理二进制
+├── pass_mgr/           # Go password manager binary
 │   ├── src/
 │   │   └── main.go
 │   └── go.mod
-├── pcexec/            # TypeScript 安全执行工具
+├── pcexec/            # TypeScript safe execution tool
 │   ├── src/
 │   │   └── index.ts
 │   ├── package.json
 │   └── tsconfig.json
-├── safe-restart/      # TypeScript 安全重启模块
+├── safe-restart/      # TypeScript safe restart module
 │   ├── src/
 │   │   ├── index.ts
 │   │   ├── status-manager.ts
@@ -93,35 +99,40 @@ PaddedCell/
 │   │   └── slash-commands.ts
 │   ├── package.json
 │   └── tsconfig.json
-├── docs/              # 文档
-├── PROJECT_PLAN.md    # 项目计划
-├── AGENT_TASKS.md     # 任务清单
-└── README.md
+├── docs/              # Documentation
+├── PROJECT_PLAN.md    # Project plan
+├── AGENT_TASKS.md     # Task list
+├── README.md          # This file (English)
+└── README.zh-CN.md    # Chinese version
 ```
 
-## 开发
+## Development
 
 ```bash
 # Clone
 git clone https://git.hangman-lab.top/nav/PaddedCell.git
 cd PaddedCell
 
-# Build pass_mgr (需要 Go)
+# Build pass_mgr (requires Go)
 cd pass_mgr
 go build -o pass_mgr src/main.go
 
-# Build pcexec (需要 Node.js)
+# Build pcexec (requires Node.js)
 cd ../pcexec
 npm install
 npm run build
 
-# Build safe-restart (需要 Node.js)
+# Build safe-restart (requires Node.js)
 cd ../safe-restart
 npm install
 npm run build
 ```
 
-## 开发分支
+## Branches
 
-- `main` - 主分支
-- `dev/zhi` - 当前开发分支
+- `main` - Main branch
+- `dev/zhi` - Development branch
+
+## License
+
+MIT