feat(web,cms): add quiz-button section component

[Kneesal]

Background

The experience pages need a quiz button section component that opens a modal with an embedded quiz iframe. The button has a distinctive animated gradient style (orange/amber/red mesh gradient) with a "QUIZ" badge and arrow icon.

Expected outcome

A fully functional quiz-button component:

• CMS schema (quiz-button) with buttonText and iframeSrc attributes
• Web component rendering the gradient button and opening a dialog with the iframe
• Seed data placing the button as the last block in the first section
• Fragment and renderer wiring

Acceptance criteria

• CMS schema quiz-button.json exists with buttonText (string, required) and iframeSrc (string, required)
• Quiz button is added to the section content dynamic zone
• Web component renders gradient button matching reference design
• Clicking button opens modal with iframe using iframeSrc from CMS
• GraphQL fragment created and wired into section fragment
• Section.tsx SectionContentRenderer handles ComponentSectionsQuizButton
• Seed data places quiz button as last block in first section
• Mesh gradient animation added to globals.css

Possible solution(s)

1. Create CMS schema, web component (QuizButton + QuizModal), fragment, and seed data following existing section patterns

References

• Existing section component patterns in apps/cms/src/components/sections/
• Reference design from previous project

[Kneesal]

Execution Plan

1. CMS: Create quiz-button.json schema — buttonText (string, required) + iframeSrc (string, required)
2. CMS: Add sections.quiz-button to section.json dynamic zone
3. CMS: Update schema.graphql — Add ComponentSectionsQuizButton type to SectionContentDynamicZone and GenericMorph unions
4. CMS: Add seed data via bootstrap() in src/index.ts — Place quiz button as last block in first section
5. Web: Create QuizButton.tsx component — Gradient button + modal with iframe
6. Web: Create quiz-button-section.ts fragment — GraphQL fragment for quiz button fields
7. Web: Wire fragment — Add to section.ts spread, export from fragments/index.ts
8. Web: Add to Section.tsx renderer — Handle ComponentSectionsQuizButton in SectionContentRenderer
9. Web: Add mesh gradient animation to globals.css
10. Codegen — Regenerate GraphQL types