Configure markdown files to open in preview mode by default

[cbochs]

Check for existing issues

• [X] Completed

Describe the feature

I know you can open a file at a specific line with the zed cli with:

zed README.md:111

It would be great if you could open a markdown file could be opened (by default) in "preview" mode instead of the editable document? In VSCode this can be accomplished with workspace.editorAssociations:

  "workbench.editorAssociations": {
    "*.md": "vscode.markdown.preview.editor"
  },

If applicable, add mockups / screenshots to help present your vision of the feature

No response