重构：文件系统模块化架构，优化应用启动流程

internal/dbclient/mongo.go

@@ -4,7 +4,8 @@ import (
 	"context"
 	"fmt"
 	"net/url"
-	"time"
+
+	"go-desk/internal/common"
 
 	"go.mongodb.org/mongo-driver/bson"
 	"go.mongodb.org/mongo-driver/mongo"
@@ -107,11 +108,11 @@ func tryConnectMongo(config *MongoConfig, authSource, authMechanism string) (*Mo
 	// 客户端选项
 	clientOptions := options.Client().
 		ApplyURI(uri).
-		SetConnectTimeout(5 * time.Second).
-		SetServerSelectionTimeout(5 * time.Second)
+		SetConnectTimeout(common.TimeoutConnect).
+		SetServerSelectionTimeout(common.TimeoutConnect)
 
 	// 创建客户端
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), common.TimeoutConnect)
 	defer cancel()
 
 	client, err := mongo.Connect(ctx, clientOptions)
@@ -169,7 +170,7 @@ func TestMongoConnectionWithOptions(host string, port int, username, password, d
 // Close 关闭连接
 func (c *MongoClient) Close() error {
 	if c.client != nil {
-		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		ctx, cancel := context.WithTimeout(context.Background(), common.TimeoutConnect)
 		defer cancel()
 		return c.client.Disconnect(ctx)
 	}