Bring back LongSlow

[johnthebrick9]

Brings back the LONG_SLOW preset as it is useful in areas with fewer nodes and very low density.

Related Issue

[CLAassistant]

All committers have signed the CLA.

[johnthebrick9]

I want to add that while I understand some would like to remove slower presets as the network get more dense, areas like the one I am in can't get more dense dues to limitations and I believe I am not the only one using meshtastic in such area.
This is why I believe this preset should stay and there is not reason to remove it since unlike LongVerySlow, LongSlow is perfectly usable.

[fifieldt]

Hi @johnthebrick9, can you tell us a bit more about your mesh?

We based the decision to deprecate LongSlow based on usage data from the apps, mqtt, and anecdotal work in discord.

[johnthebrick9]

Hi @johnthebrick9, can you tell us a bit more about your mesh?
I'm using Meshtastic in the mountains with a few other users. Most hops go through nodes that are within line of sight, but some links span very long distances or face obstacles. We chose the LONGSLOW preset because it's the only one that remains reasonably reliable while hiking or when nodes are partially obstructed.