dolt init fails if dolt config is run without global arguments

[societal-sandpaper]

I think there may be one or two separate bugs covered by this.

Overall bug: It seems to be impossible to make a new repo on dolthub, and then initialize it with a non-global email/name config.

Reproduction

1. Create a dolthub repo
2. Bug 1: Try to clone the repo right away. Get an error like "clone failed; remote at that url contains no Dolt data". GitHub adds an initial empty commit which allows you to clone a repo right away (very helpful).
3. Emotionally accept that you can't clone it right away.
4. mkdir new-repo ; cd new-repo
5. dolt init
6. See error message (acceptable): Author identity unknown. Run dolt config... .... Omit --global to set the identity only in this repository.
7. Run the non-global dolt config commands: dolt config --add user.email ... and dolt config --add user.name ...
8. Bug 2: Try dolt init. See that it fails: Failed to initialize directory as a data repo. .dolt directory already exists at '.'
9. Try dolt remote add origin .... See that it fails: The current directory is not a valid dolt repository. I suppose this is expected.

Suggested Improvements

Any of these would fix the overall . I'd suggest that all of them should be implemented:

1. Fix Bug 1: Allow cloning a brand-new repo. (Tracked in dolt shouldn't create an init commit #2361)
2. Fix Bug 2: Allow dolt init if the only thing in the .dolt folder of a repo is a config.json.

[timsehn]

Part of this is a long standing feature request: #2361

The non-global thing is a great find and I'll repurpose this bug for that. @jycor will fix that today.

[timsehn]

I also created a dolthub-issue for cloning a new/empty database: dolthub/dolthub-issues#570

[societal-sandpaper]

All sounds reasonable, thanks!

[jycor]

I have a PR in progress that allows dolt init to work when there's just a config.json in .dolt.
#8838

A potential workaround is:

$ dolt init --name 'local_user' --email 'user@local.com'
Successfully initialized dolt data repository.

$ dolt log
commit fs4mir7f918st5975popfj1vjjc6gp5l (HEAD -> main) 
Author: local_user <user@local.com>
Date:  Fri Feb 07 14:26:10 -0800 2025

        Initialize data repository

$ cat .dolt/config.json 
{"user.email":"user@local.com","user.name":"local_user"}