Add the Quiz Card tutorial template (tutorial-quiz-card) #73

Part of #5. "Quiz of the day" cards are popular with educators. This is also the first template to use the toggle field type.

Idea
A "Quiz" pill plus a category pill at the top, then the question in large type. Below are 4 option boxes in a 2x2 layout (two flex rows), each with a letter badge (A to D). When "Show answer" is on, the correct option gets an accent background and a "Correct" tag.

Template details

• File: src/templates/tutorial/quiz-card.ts, id tutorial-quiz-card
• Fields: commonFields.title (question), optionA to optionD (text), correctOption (select: A / B / C / D), showAnswer (toggle, default false), commonFields.category, commonFields.bgColor, commonFields.accentColor, commonFields.textColor

Where to look

• Closest reference: src/templates/product/feature-grid.ts (2x2), src/templates/tutorial/difficulty-badge.ts (select field)
• Toggle UI: src/components/editor/ToggleSwitch.tsx

Acceptance criteria

• showAnswer is parsed as params.showAnswer === true || params.showAnswer === 'true' (the API passes strings)
• The toggle works in the editor
• Re-exported in src/templates/tutorial/index.ts and registered in the Tutorial block of src/templates/registry.ts
• Meets the shared template checklist in Add new card-style OG image templates #5

One template per contributor at a time, so more people get a chance.

Want to work on this? Comment below and I'll assign it to you. Please take one issue at a time, branch off dev, and open your PR against dev with Closes #<this issue number>.