feat: 重构前后端架构，添加Go后端和Python Agent服务

- 新增 Go 语言后端服务(server/)，包含用户认证、Agent管理、数据库连接等API
- 新增 Python Agent 服务(agent/)，实现Agent核心逻辑和工具集
- 前端从原生HTML迁移到Vue.js框架(web/src/)
- 添加 Docker Compose 支持(docker-compose.yml)
- 添加项目架构文档(docs/ARCHITECTURE.md)
- 添加环境变量示例(.env.example)和本地启动脚本(start-local.ps1)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/internal/handler/system_helper.go

@@ -0,0 +1,60 @@
+package handler
+
+import (
+	"github.com/shirou/gopsutil/v3/cpu"
+	"github.com/shirou/gopsutil/v3/mem"
+	"x-agents/server/internal/model"
+)
+
+func getCPUPercent() (float64, error) {
+	percent, err := cpu.Percent(0, false)
+	if err != nil {
+		return 0, err
+	}
+	if len(percent) > 0 {
+		return percent[0], nil
+	}
+	return 0, nil
+}
+
+func getCPUCoreCount() (int, error) {
+	count, err := cpu.Counts(false)
+	if err != nil {
+		return 0, err
+	}
+	return count, nil
+}
+
+func getCPUModelName() (string, error) {
+	info, err := cpu.Info()
+	if err != nil {
+		return "Unknown", err
+	}
+	if len(info) > 0 {
+		return info[0].ModelName, nil
+	}
+	return "Unknown", nil
+}
+
+func getMemoryInfo() (*model.MemoryInfo, error) {
+	v, err := mem.VirtualMemory()
+	if err != nil {
+		return nil, err
+	}
+
+	// 计算使用率
+	percent := 0.0
+	if v.Total > 0 {
+		percent = float64(v.Used) / float64(v.Total) * 100
+	}
+
+	return &model.MemoryInfo{
+		Total:       v.Total,
+		Used:        v.Used,
+		Available:   v.Available,
+		Percent:     percent,
+		TotalGB:     float64(v.Total) / 1024 / 1024 / 1024,
+		UsedGB:      float64(v.Used) / 1024 / 1024 / 1024,
+		AvailableGB: float64(v.Available) / 1024 / 1024 / 1024,
+	}, nil
+}