Settings icon isn't retained when opening workspace

[mirnovov]

When opening a workspace, any customisations to the settings button icon aren't retained and the ability to modify it by clicking is lost.

This also affects the Homepage plugin as it uses workspaces internally, cf. mirnovov/obsidian-homepage#103

[gfxholo]

Ooo great catch, thank you for passing this on! This also kills the Help & Pin icons on desktop & tablet. I guess they need to be re-hooked after every layout-change event.