Create helpers from automation editor

[karwosts]

Proposed change

Often when writing an automation, I will discover I need some additional helper as part of the logic flow. Instead of having to leave the automation page, I thought it might be nice if we can have an option to create a new helper right where it is used, requiring less navigating and steps to accomplish the goal.

I considered a couple different ideas, like maybe adding Create Helper option to the quick bar, or adding a small button somewhere on the automation page, but for now I'm proposing a new option in the entity picker, for service calls of the 9 helper domains, as that I think is where they might most typically be wanted, and it nicely pre-fills the target picker when you create it.

This could possibly be expanded further, for creating more types of helpers in more places, but this felt like a reasonable start.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (thank you!)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example configuration

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue or discussion:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io