fix(field): say a title is rich text limited to one heading

[angeloashmore]

Resolves: #275

Description

The CLI states the single-heading title convention only in the EXAMPLES section of prismic field add rich-text --help. An agent asked for a title reads prismic field add text --help instead, never opens the rich text help, and adds the title as text.

This PR puts the convention on both help surfaces the agent reads, and the eval goes from 5 of 18 trials to 10 of 10.

Checklist

• If my changes require tests, I added them.
• If my changes affect backward compatibility, it has been discussed.
• If my changes require an update to the CONTRIBUTING.md guide, I updated it.

Preview

prismic field add text --help:

Add a text field to a slice or custom type.

A text field holds a short plain string with no formatting.

For a title or a heading, rich text limited to a single heading block
is usually a better fit:

  prismic field add rich-text title --to-type blog_post --allow heading1 --single

How to QA ¹

In a container or a disposable VM:

$ node --run build
$ IS_SANDBOX=1 EVAL_TRIALS=10 PRISMIC_ALLOW_EVALS=true node --run evals -- \
    evals/design-sensible-models.eval.ts \
    -t "models a title as single-heading rich text|models a testimonial slice from a text description"

The testimonial eval is the counter-check. It wants a text field for the author name, so it catches this text pushing plain strings into rich text. It holds at 10 of 10.

🤖 Generated with Claude Code

https://claude.ai/code/session_01YRv7FgAiL76NgBHywdGKPC

Footnotes

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