Support link with column numbers in the markdown editor

[acecilia]

Hi 👋

The ticket https://github.com/microsoft/vscode/issues/40140 added support for following markdown links that specify local paths including line numbers.

Existing behaviour:

Given two files and their content:

a.md:

[b](./b.md#L3)

b.md:

1
2
3ABC
4
5

Clicking on link ./b.md#L3 in the markdown editor opens b.md with the cursor at the beginning of line 3.

Requested behaviour:

With this ticket I would liken to request support for adding also column numbers, so:

a.md:

[b](./b.md#L3C3)

b.md:

1
2
3ABC
4
5

Clicking on link ./b.md#L3C3 in the markdown editor should open b.md with the cursor position in line 3, letter B.

Thanks! 🙏