Further Simplify Flags

[nathaniel-may]

Describe the feature

When adding a new flag, there are many places you must put the name of your flag in a very boiler platey fashion. Since adding and removing new flags is a very common user interface change that we want to get right, I would like to slightly rearrange the flow of flags so that you define the information once, and the rest of the code references that definition to set all the appropriate factors.

Describe alternatives you've considered

We could also just not do this, because the boiler plate isn't really that bad.

Additional context

You have to remember to put in all the argparse-specific parameters, defaults, and global values which are all defined in different places.

PR#3839 made huge improvements to the flag system already.

Who will this benefit?

dbt contributors and developers.

[gshank]

I suspect that we're going to see some changes in flag handling with the new server work. Not sure where we'll end up on that, so we might wait until we see the requirements there to address this.

[github-actions]

This issue has been marked as Stale because it has been open for 180 days with no activity. If you would like the issue to remain open, please remove the stale label or comment on the issue, or it will be closed in 7 days.

[github-actions]

This issue has been marked as Stale because it has been open for 180 days with no activity. If you would like the issue to remain open, please remove the stale label or comment on the issue, or it will be closed in 7 days.

[github-actions]

Although we are closing this issue as stale, it's not gone forever. Issues can be reopened if there is renewed community interest; add a comment to notify the maintainers.