[Checkout Editor] Default values in toml settings

[gil--]

Please list the related package(s)

checkout-ui-extensions

If this related to specific APIs or components, please list them here

For example:

[settings]
  [[settings.fields]]
  key = "title"
  type = "single_line_text_field"
  name = "Title (optional)"
  description = "Enter a title for the block."

Would have a default:

[settings]
  [[settings.fields]]
  key = "title"
  type = "single_line_text_field"
  name = "Title (optional)"
  description = "Enter a title for the block."
+ default = "Hello!!"

Is your feature request related to a problem? Please describe.

Would be nice to specify a default value for a toml input setting similar to the default attribute for theme settings.

Describe the changes you are looking for

Add ability to specify the default value for a setting via new default attribute on all input setitngs.

Describe alternatives you’ve considered

I specify a default in the extension code but it's not ideal as there's nothing selected within the checkout editor. Does not work super well if you want a checkbox selected by default for example.

[jfeuchterbc]

+1 This would be great to have

[javelpivotech]

+1 Please add it!

[bluedge]

Much needed +1

[FranciscoBejaranoBluEdgeUsa]

Absolutely necessary! +1

[CodeMan82]

This would be a great addition to the extension definitions!

[aidin]

Upvote!!

[merziy]

This would be useful, surprised it is not a thing.

[Sandor79]

Absolutely necessary! +1

[aaronkantrowitz]

Need!!!