[FEATURE] file:// markdown link to a directory should open the tree in the desktop file viewer

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

A markdown link with a file:// href to a FILE opens correctly in the desktop
app's file viewer, and offers "show in Finder" from there. The same link
pointing at a DIRECTORY (e.g. file:///Users/me/some-folder/) does not open at
all — no viewer, no Finder reveal, no error shown.

Expected: either open the folder in Finder directly, or show its contents in
the same in-app file viewer used for a single file.

Workaround in use today: link to one representative file inside the folder
instead of the folder itself, then use "show in Finder" from there.

Proposed Solution

Open the tree in the desktop file viewer for navigation of the directory.

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

File operations

Use Case Example

My ai assistant's clickable link should open the file tree in the viewer for directories that I need to navigate by structure or across multiple items.

Additional Context

_No response_