POC - Combining BW Clock and Desktop Launcher to spend less time "Loading..."

Thanks! Just merged (and also merged your similar changes for the clock) and the builds now with up to date JS really do feel a lot snappier.

Now we just need to ensure that more clocks implement Bangle.setUI({..., remove}) - just a note that I tried adding it to the ClockFace module but clocks like terminalclock add a lot of other stuff which caused it to break. I guess we could make it opt-in