fix: support for Microsoft WebDAV (AlistGo#6133 close AlistGo#6104)

* Add support for Microsoft WebDAV

* add import

server/webdav/prop.go

@@ -14,6 +14,7 @@ import (
 	"net/http"
 	"path"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/alist-org/alist/v3/internal/model"
@@ -385,6 +386,10 @@ func findLastModified(ctx context.Context, ls LockSystem, name string, fi model.
 	return fi.ModTime().UTC().Format(http.TimeFormat), nil
 }
 func findCreationDate(ctx context.Context, ls LockSystem, name string, fi model.Obj) (string, error) {
+	userAgent := ctx.Value("userAgent").(string)
+	if strings.Contains(strings.ToLower(userAgent), "microsoft-webdav") {
+		return fi.CreateTime().UTC().Format(http.TimeFormat), nil
+	}
 	return fi.CreateTime().UTC().Format(time.RFC3339), nil
 }
 

server/webdav/webdav.go

@@ -6,6 +6,7 @@
 package webdav // import "golang.org/x/net/webdav"
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"net/http"
@@ -619,6 +620,8 @@ func (h *Handler) handlePropfind(w http.ResponseWriter, r *http.Request) (status
 		return status, err
 	}
 	ctx := r.Context()
+	userAgent := r.Header.Get("User-Agent")
+	ctx = context.WithValue(ctx, "userAgent", userAgent)
 	user := ctx.Value("user").(*model.User)
 	reqPath, err = user.JoinPath(reqPath)
 	if err != nil {