NSCP review fixes: deeper pass on top of recent surgical fixes (#23)

[EfeosasereOkoro-gov]

Summary

Comprehensive review pass on the NSCP Camper Registration form addressing the 22 items in govtech-bb/projects#23 that werent covered by the recent surgical fixes on main.

Two reviewers (manual + Claude) raised issues across Critical / Significant / Minor. This PR layers the structural and framework-level changes on top of the inline copy/validation fixes already merged.

Live preview (after merge):https://govtech-bb.github.io/newforms/Prototypes/nscp-camper-registration.html

What is in this PR

Framework (assets/govbb-framework.js)

• render(preserveScroll) -- only scrolls to top on real next/back/nav. Conditional re-renders preserve scroll + restore keyboard focus to the just-clicked control.
• Radio inputs use change event (was input) and reliably restore checked state on every render.
• New _clearFieldError(el) -- clears inline error message, aria-invalid, and the matching <li> in the error summary as soon as the user fixes a field. Handles radio groups by name.
• _hidePreviousOnFirstStep now actually wired up in render().

These framework improvements benefit every prototype using govbb-framework.js, not just NSCP.

NSCP form (Prototypes/nscp-camper-registration.html)

• Flow restructure: "Choose a camp" was one long page. Split into three steps -- Choose a camp (parish/venue/topics) -> Activities and first aid -> Photos and videos.
• Emergency-contact step always visible: removed the getFlow filter that dropped the step when guardian = emergency contact. When that's the case, the page renders a confirmation-only view ("You said you are the emergency contact... change") with Continue. Total form steps stable at 11 -- fixes the 9->8 step counter jump.
• Name split: Camper / Guardian / Emergency contact each get First name / Other names (optional) / Surname instead of one Full name field. (Mirrors what was done on the centenarian form.)
• First-aid consent is now an explicit required checkbox on the new Activities page (was passive notice copy).
• DOB validation flags all three fields (Day/Month/Year) when any are missing -- error summary link still focuses Day.
• Medication Authorisation Form: download link added above the upload widget.
• Confirmation page: email confirmation mention, "Print or save this page" button, "Register another child" link.
• Sex / Gender consistency: review page reads "Sex".
• Checkbox alignment: all 14 checkboxes (curriculum + first-aid + conduct) top-aligned with consistent spacing.
• Topics hint: clarifies at-least-one requirement.

Relationship to the recently-merged fixes (#1)

The commit on main (570773b) made small surgical fixes to 6 items in the NSCP HTML. Two of those overlap with this PR:

• Dietary conditional on meals=Yes -- Gavin used inline conditional logic; this PR uses the framework's data-show-when-name pattern (so the same conditional reveal style as every other Yes/No in the form). Behaviour is the same.
• "Error:" title prefix cleared on resolution -- Gavin cleared it on form pages; this PR clears it from the framework's _clearFieldError so it works everywhere automatically.

Both overlaps should be reviewed; if the framework-level versions look cleaner, the inline ones can come out in a follow-up. No functional regression either way.

Test plan

• Click any Yes/No radio on the Medical & health step -- page does NOT scroll to top, focus stays on the radio
• Continue without selecting illness -- error shows; click "Yes" -- error clears immediately
• Leave DOB blank, click Continue -- Day / Month / Year all show red
• Step 1 has First name / Other names / Surname inputs (not "Full name")
• On Meals, select Yes -> dietary appears; No -> dietary hides; navigating forward + back preserves the selection
• Choose "I am the emergency contact: Yes" -> still see an emergency-contact step (confirmation-only view), counter stays at "Step X of 11"
• Activities page has an explicit first-aid consent checkbox; Continue without ticking shows an error
• Confirmation page shows email mention, Print button, and Register another child link
• Other prototypes (terms-leave, textbook-grant, exam-fee-refund) still work -- the framework changes shouldn't have broken them

[amazon-inspector-n-virginia]

⏳ I'm reviewing this pull request for security vulnerabilities and code quality issues. I'll provide an update when I'm done

[amazon-inspector-n-virginia]

✅ I finished the code review, and didn't find any security or code quality issues.