Unresolved References Issue with Subdirectories in VSCode Plugin

[TieWay59]

Hello @Feel-ix-343 ,

Issue Description:
When using the markdown-oxide plugin in VSCode, any link (which translates to "bidirectional links" or "backlinks") that are located in subdirectories is marked as unresolved ("Unresolved Reference" as shown in the screenshot). This happens regardless of whether the links are correctly set up and the files exist.

Reproduction Steps:

1. Install the markdown-oxide VSCode extension.
2. Create a markdown file with a bidirectional link to a file located in a subdirectory.
3. Observe that the link is marked as unresolved in the VSCode editor.

Expected Behavior:
The bidirectional links should be recognized and resolved correctly, even if they point to files within subdirectories.

Current Behavior:
The links are marked as unresolved, which is incorrect and disrupts the workflow for managing backlinks.

Environment:

• markdown-oxide plugin version: 1.1.0
• Operating System: win10 & ubuntu22

Additional Information:
I have ensured that the links are correctly formatted and that the files they reference exist. I have also checked the plugin settings and ensured that they are configured correctly.

Screenshot:

Thank you for your attention to this matter.

[Feel-ix-343]

(hey I am able to check this out this weekend)

[Feel-ix-343]

(I didn't get to it sorry!)