Feature request: Move graphs around by dragging the mouse

[ChristianCiach]

Summary

Allow moving/scrolling the "Tree" and "Network" views by dragging the mouse while holding down a mouse button (drag and drop style).

Motivation

We are new to ArgoCD and our developers greatly enjoy the UI to monitor their applications.

However, if an application gets large, the "Tree" and "Network" views will quickly overflow horizontally. While scrolling vertically is easily done with the mouse wheel, scrolling horizontally is much more cumbersome (most people don't know that holding the shift-key changes to horizontally scrolling).

Most of our developers (me included) instinctively tried to move the the graph view by holding down the left or middle mouse button and then moving the mouse around, but unfortunately this isn't currently supported. You have to use the browser native controls (scrollbars) to move the view, which feels very outdated.

There are tons of precedences for tools that allow scrolling by drag-and-drop, for example:

• https://maps.google.com (by holding down the left mouse button)
• https://app.diagrams.net (by holding down the middle mouse button)

Proposal

I would suggest to allow moving the views while holding down the left mouse button. At first I was worried that this could conflict with text-selection, but actually, selecting text inside the "Tree" and "Network" views is currently annoying anyway. While you currently can select text using the left mouse button, this will immediately open the details-view of the selected element on button release. Holding the left mouse button to move the views around would probably feel most intuitive for most users.