feat(demo): add “CoinSpark” demo under minikit/Coin-your-idea

[Elishaokon13]

This PR introduces a brand-new demonstration frame called CoinSpark in the minikit/Coin-your-idea directory. CoinSpark showcases:

• AI-powered idea generation with OpenAI
• On-chain minting via Zora’s Coins SDK
• Frame integration (account association & notifications) powered by OnchainKit & MiniKit
• Persistent storage in MongoDB
• Background notifications via Upstash Redis
• Real-time transaction feedback with Etherscan links
• Dark/light theming via Tailwind CSS

All source files, API routes, UI components, and styles are contained under the new minikit/Coin-your-idea/ folder structure.

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📂 Changed Files

• Added directory: minikit/Coin-your-idea/
  • README.md (comprehensive demo docs)
  • app/ (Next.js pages & components)
  • lib/ (helpers for MongoDB, Wagmi, notifications, Redis)
  • public/, plus postcss.config.js, tailwind.config.ts, next.config.mjs
  • package.json, tsconfig.json, next-env.d.ts, yarn.lock

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Please review and let me know if you’d like any tweaks before merging!

[wbnns]

Thanks for contributing! Adding this to our backlog, pending to be reviewed. 👍

[Elishaokon13]

Thank you Wills! I will be expecting feedback soon.