feat: 初始化项目基础架构和核心功能

- 添加项目基础结构：Cargo.toml、.gitignore、设备UID和密钥文件
- 实现前端Vue3项目结构：路由、登录页面、设备管理页面
- 添加核心协议定义(crates/protocol)：设备状态、资产、USB事件等
- 实现客户端监控模块：系统状态收集、资产收集
- 实现服务端基础API和插件系统
- 添加数据库迁移脚本：设备管理、资产跟踪、告警系统等
- 实现前端设备状态展示和基本交互
- 添加使用时长统计和水印功能插件

migrations/002_assets.sql

@@ -0,0 +1,42 @@
+-- 002_assets.sql: Asset management tables
+
+CREATE TABLE IF NOT EXISTS hardware_assets (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    device_uid      TEXT NOT NULL REFERENCES devices(device_uid) ON DELETE CASCADE,
+    cpu_model       TEXT,
+    cpu_cores       INTEGER,
+    memory_total_mb INTEGER,
+    disk_model      TEXT,
+    disk_total_mb   INTEGER,
+    gpu_model       TEXT,
+    motherboard     TEXT,
+    serial_number   TEXT,
+    reported_at     TEXT NOT NULL DEFAULT (datetime('now')),
+    updated_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    UNIQUE(device_uid)
+);
+
+CREATE TABLE IF NOT EXISTS software_assets (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    device_uid      TEXT NOT NULL REFERENCES devices(device_uid) ON DELETE CASCADE,
+    name            TEXT NOT NULL,
+    version         TEXT,
+    publisher       TEXT,
+    install_date    TEXT,
+    install_path    TEXT,
+    updated_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    UNIQUE(device_uid, name, version)
+);
+
+CREATE TABLE IF NOT EXISTS asset_changes (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    device_uid      TEXT NOT NULL REFERENCES devices(device_uid) ON DELETE CASCADE,
+    change_type     TEXT NOT NULL CHECK(change_type IN ('hardware', 'software_added', 'software_removed')),
+    change_detail   TEXT NOT NULL,
+    detected_at     TEXT NOT NULL DEFAULT (datetime('now'))
+);
+
+-- Indexes
+CREATE INDEX IF NOT EXISTS idx_software_device ON software_assets(device_uid);
+CREATE INDEX IF NOT EXISTS idx_asset_changes_time ON asset_changes(detected_at);
+CREATE INDEX IF NOT EXISTS idx_asset_changes_device ON asset_changes(device_uid);