Linter should ignore markdown links

Hi, not sure if this is a bug or more of a feature request, but I've reported it as a bug - feel free to change if needed

**Describe the bug**
Linter should not emit an error within the link part of a markdown link. Currently this happens when the link contains spaces only

**To Reproduce**
1. Create a markdown link that links to a file with spaces and a typo in the link
- e.g. `[My link](./my dokument.md)`
2. See an error
**Expected behavior**

Markdown links should never emit errors in the link part (between `()`) - not sure if this should be the default behavior or be behind an option

**Screenshots**

**Platform**
`helix 25.07.1 (a05c151b)` with `harper-ls 1.4.1`

**Additional context**
Add any other context about the problem here.

Reproduce the report with `[My link](./my dokument.md)` in Harper and inspect the markdown-link linting path. Confirm which diagnostics are emitted inside the `()` target; done means that link portion produces no errors while checks outside it remain intact. The issue identifies no files or tests.

Written by the indexing model from the issue text.