FR: Add mini map to flowfuse flow renderer

[AllanOricil]

Description

Currently, when flows are rendered far away from the initial state (top left corner) of the canvas it is hard to find where the flow is located within the boundaries of the canvas (8000x8000). If there was a mini map like the one we see in Node-RED, this issue would be sorted.

https://discourse.nodered.org/t/sharing-flows-on-the-forum-just-get-prettier/97957?u=allanoricil

Requested By

• Super Allan Oricil

[Steve-Mcl]

An alternative approach to consider before implementing a mini map is suggested in #48
I currently have no opinion for or against either approach