Switch incline_steps to radio field

[matkoniecz]

With this change just selector is not enough at all.

iD, maybe other data consumers, really should get request along 'For incline=up/down show which end is up' lines

maybe such hint should be part of iD tagging schema? Which other fields would benefit from such hint?

Description, Motivation & Context

see #2049

Related issues

part of #2049

Links and data

Relevant OSM Wiki links:

• …

Relevant tag usage stats:

…

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[matkoniecz]

after this is merged: create mentioned iD issue, maybe schema builder issue, maybe GoMap!! issue, maybe for other data consumers

take look at #2049 (comment) an open next radio PR

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[matkoniecz]

note: steps start suffering from field taking more space

steps

https://pr-2141--ideditor-presets-preview.netlify.app/id/dist/#locale=en&map=21.17/48.83957/2.59073&disable_features=boundaries&background=fr.ign.bdortho&id=w1369009882

ladder

https://pr-2141--ideditor-presets-preview.netlify.app/id/dist/#locale=en&map=22.55/52.16956/21.06761&disable_features=boundaries&background=MAPNIK&id=w1420792996

[matkoniecz]

more to check: https://github.com/search?q=repo%3Aopenstreetmap%2Fid-tagging-schema%20incline_steps&type=code

[matkoniecz]

https://pr-2141--ideditor-presets-preview.netlify.app/id/dist/#locale=en&map=22.34/50.06630/19.94629&disable_features=boundaries&background=fr.ign.bdortho&id=w766325845