docs: update authorise page based on reviewer feedback

[nat294]

Summary

• Fix H6 headings appearing smaller than bold text by adding .markdown h6 { font-size: 1rem } to custom.css
• Add missing "Guardrail Type" heading before the type-specific sections
• Restructure guardrail sections to eliminate repeated content — shared configuration (Toggles, Activity Type, Fields to Check, Timeout, Retry) is now documented once.
• Add error handling callout in Behavioral Rules linking to the SDK Error Handling page.
• Add wizard completion tip warning users to fill all required fields before clicking Create Rule.

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[ash-krnl]

Looks good to me, just make sure the toggles are working on docausaurus

[tonyopenbox]

Great!

I think we also need to pass this back to the dev team to add validation to each step to provide a more useful error message.

[nat294]

Yes, I will inform them in backlog to maybe add useful message on UI for users but anyway, thanks Tony :D

[nat294]

Looks good to me, just make sure the toggles are working on docausaurus

Thanks @ash-krnl , I tested locally with npm start and it seems work on the side.