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

crates/client/src/asset/mod.rs

@@ -0,0 +1,54 @@
+use csm_protocol::{Frame, MessageType, HardwareAsset};
+use std::time::Duration;
+use tokio::sync::mpsc::Sender;
+use tracing::{info, error};
+use sysinfo::System;
+
+pub async fn start_collecting(tx: Sender<Frame>, device_uid: String) {
+    let interval = Duration::from_secs(86400); // Once per day
+
+    // Initial collection on startup
+    if let Err(e) = collect_and_send(&tx, &device_uid).await {
+        error!("Initial asset collection failed: {}", e);
+    }
+
+    loop {
+        tokio::time::sleep(interval).await;
+
+        if let Err(e) = collect_and_send(&tx, &device_uid).await {
+            error!("Asset collection failed: {}", e);
+        }
+    }
+}
+
+async fn collect_and_send(tx: &Sender<Frame>, device_uid: &str) -> anyhow::Result<()> {
+    let hardware = collect_hardware(device_uid)?;
+    let frame = Frame::new_json(MessageType::AssetReport, &hardware)?;
+    tx.send(frame).await.map_err(|e| anyhow::anyhow!("Channel send failed: {}", e))?;
+    info!("Asset report sent for {}", device_uid);
+    Ok(())
+}
+
+fn collect_hardware(device_uid: &str) -> anyhow::Result<HardwareAsset> {
+    let mut sys = System::new_all();
+    sys.refresh_all();
+
+    let cpu_model = sys.cpus().first()
+        .map(|c| c.brand().to_string())
+        .unwrap_or_else(|| "Unknown".to_string());
+
+    let cpu_cores = sys.cpus().len() as u32;
+    let memory_total_mb = sys.total_memory() / 1024 / 1024; // bytes to MB (sysinfo 0.30)
+
+    Ok(HardwareAsset {
+        device_uid: device_uid.to_string(),
+        cpu_model,
+        cpu_cores,
+        memory_total_mb: memory_total_mb as u64,
+        disk_model: "Unknown".to_string(),
+        disk_total_mb: 0,
+        gpu_model: None,
+        motherboard: None,
+        serial_number: None,
+    })
+}