exp init: change ui prompts structure and output

[skshetry]

• ❗ I have followed the Contributing to DVC checklist.

• 📖 If this PR requires documentation updates, I have created a separate PR (or issue, at least) in dvc.org and linked it here.

Closes #7130 and closes #6446.

Screenshots

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[skshetry]

All of the outputs have been moved out of dvc.experiments.init now (except what we need for prompts) to commands.

[dberenbaum]

Nice! It works really well, and I think the simplified output text is better. We can probably even drop the line with the link at the end.

I'm not sure we need so much styling specific to this command. I think we can even further simplify and make it more consistent. What do you think of this (from https://github.com/dberenbaum/dvc/tree/exp-init-ui)?

Light background:

[skshetry]

I'm not sure we need so much styling specific to this command. I think we can even further simplify and make it more consistent. What do you think of this (from https://github.com/dberenbaum/dvc/tree/exp-init-ui)?

That makes sense, I went a bit over the top. I want to keep the last message as "You can now run your experiment" as
it's more of a tips/hints than a command. Also, first two lines being a status output, . (period) should not be there.

[skshetry]

@dberenbaum, I’m merging this. I will iterate on top if there’s anything need to change.

[dberenbaum]

Looks good @skshetry! I think we can call this done for now.