Make default 'Required messages' reflect GDS guidance

[siliconmeadow]

Would it be possible to update required messages to reflect the GDS guidance?

We’re aiming to align our validation wording with the GDS error-message pattern:

https://design-system.service.gov.uk/components/error-message/

GDS examples use short, direct, action-focused instructions such as:

Enter a postcode
Enter town or city
Enter address line 1

Updating our message to follow this style will keep it clear, consistent, and accessible while matching GDS standards.

Originally posted by @AnthonyDotcom2000 in 6a4b52a

[ekes]

See also #62 (comment)

[ekes]

The default that will be used on fields not supplied by this module is usual the Drupal one: @name field is required (where @name is the field name set on the form element).
So if anything it feels like this module should use the same defaults as every other field is going to use? Otherwise, unless you've decided to set all fields, if it's possible, there's going to be a mismatch in messages?

It would be nice if this module could make the default for all fields to be GDS style Enter @name. But I can't see that's possible in English: Enter an address Enter a postcode Enter address line 1 Enter a full name Enter an email address...

[ekes]

Added the logical follow-up on the address set required message issue #62 (comment)

[ekes]

How's this hit you https://git.drupalcode.org/project/localgov_forms/-/merge_requests/4

(it doesn't work yet with Address field specifically because that's still hard coded, but changing that hard coding to respect the #required_error if set would then fix it here too... adding the option to set the #required_error in the UI would still be an issue for #62).