Add button to open docs online

### Godot version

v4.7.mychanges.custom_build [56751353c]

### VS Code version

1.119.0

### Godot Tools VS Code extension version

2.6.1

### System information

Arch Linux

### Problem statement

I want to be able to open the online docs when mainly working in vscode. The normal godot editor has the button to "open in online docs" when viewing a docs page

### Proposed solution

Add a button or link on docs pages to "open in online docs"