Feature Request - Snippets (like VSCode)

I think a feature named snippets, similar to templates, should be created for insertable templatized content. It should also include placeholder support. Much like a vscode or intellij "snippet".

Using vscode as a functional and designed example:


Notice the ability to autocomplete and placeholders:
![image](

And notice the view to see what text would be inserted:
![image](

VSCode has many other nice snippet features such as tab stops, presenting choices, and inserting common variables, all for placeholders.

In VSCode the autocomplete is automatic as you type, but in Outline it may make sense to only present the snippets upon typing /snippets or a shortened version like //.

There is another Snippets suggestion, but I don't think the name follows closely with conventionally accepted terminology around the word "snippets" in editors and websites.