指定根目錄用戶複製連結

### Please make sure of the following things

- [x] I have read the [documentation](https://alist.nn.ci).
- [x] I'm sure there are no duplicate issues or discussions.
- [x] I'm sure this feature is not implemented.
- [x] I'm sure it's a reasonable and popular requirement.

### Description of the feature / 需求描述

如果指定根目錄，複製連結的路徑會是指定根目錄後的路徑
例如登入user1的情況下，/user1是該用戶指定的根目錄
對實際/user1/aaa目錄(此時登入對該用戶而言是/aaa)的連結複製連結會是http(s)://domain/aaa

但如果是複製目錄內文件的下載連結
卻能夠正確的從/目錄獲取連結
例如/user1/aaa/bbb.txt
/user1是該用戶指定根目錄的情況下，複製下載連結則是正確的http(s)://domain/user1/aaa/bbb.txt

希望能夠讓複製連結的時後可以有選項或是直接與複製下載連結一樣
複製正確的/user1/aaa.txt，因為會複製連結，通常也是有匿名分享的目的

### Suggested solution / 实现思路

_No response_

### Additional context / 附件

_No response_