Keep a list of recently used plugins in app state

[jacobwod]

This is an idea I got: using Hajk on small screens usually means a lot of multi-tasking between the different tools (Layerswitcher->Turn on some layers->Close->Open Measure->Do some measuring->Realise you need another layer->Close Measure->Open LayerSwitcher->etc etc…)

I think it would be really useful to have some kind of UI element with the 3-4 most recently used plugins easily available somewhere on screen.

Before we do that, we need a mechanism that tracks and keeps a history of recently activated plugins.

This is what this feature is about.

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Edit: I've expanded this feature to also include the UI part. Here's a video of the work-in-progress.

Skarminspelning.2022-09-16.kl.08.59.13.mov

[jacobwod]

Taking this a bit further, I'm about to implement a SpeedDial component that will keep track of 4-5 most recently used plugins and allow easy access to them.

A quick and rough illustration (don't mind the colors/icons/placement etc):

[jacobwod]

I guess we have to rethink the UI for small viewports…

[jacobwod]

Given the problem above, what about this: we invoke the same logic for plugins rendered as control buttons, as we do for plugins rendered as widget buttons. I.e. on small viewports, we ignore target: "control" (just as we ignore target: "left"|"right") and put those plugins in Drawer (as if they had target: "toolbar", basically). What do you think @Hallbergs, @jesade-vbg?