Write a changeset tag that says whether a user has completed the walkthrough

[bhousel]

I've spent a lot of time on improving the walkthrough (#3921). It might be interesting to know whether new users are actually doing the walkthrough or not.

For example, if we see a new user making some interesting pattern of mistakes, and we know they did complete the walkthrough, we can improve the walkthrough to address those mistakes.

If we see that they didn't do the walkthrough, we can ask them to complete the walkthrough in a changeset comment when we review their edits.

Thoughts?

[pnorman]

Do we reliably have this information? I've been asked several times to do the walkthrough. I suppose in the case of new users it might be valuable because it'd most likely be accurate.

[bhousel]

We don't have this information now. Instead we just set a flag in the browser's local storage if the user has never used iD before. But:

• we could start storing things in the user's OSM profile (see Store preferences in OSM profile with fallback to localStorage #3002)
• we do know from the OSM API if a user has never saved an edit before

[pnorman]

I'd go for #3002 and store walkthrough state server-side.