fix: preserve supporter choice intake UI

[afaryy]

What changed

• Preserves the browser-acceptance supporter question, choices, help text, and radio layout.
• Renders both support_contacts and information_sharing_consent with that approved choice group.
• Adds a regression test for the alternate API field.

Verification

• npm test: 32 passed
• npm run lint
• npm run build
• uv run pytest: 281 passed