Copy SEO Startup?

Build me a Marketing web app like SEO Startup.

SEO Startup does: Selling a SEO startup. Private message me for more information. All clients are billed at the same date at the end of the month which is why revenue drops before the end of each month. It reportedly makes about $24k/mo, so the core idea clearly has demand — I want a lean version I can run and charge for.

Start from the open-source project cnych/seo-mcp (https://github.com/cnych/seo-mcp) — reuse what fits, strip its branding, and build the specifics below on top of it.

Requirements:
- Enter a domain/keyword → return keyword ideas, difficulty, and SERP snapshot.
- On-page audit (title/meta/headings/links) with prioritized fixes.
- Rank tracking over time and a simple project dashboard.
- AI: generate optimized meta + content briefs.

Also:
- Clean, modern, responsive UI with a thoughtful landing page.
- Email/password auth and a simple paid tier (Stripe test mode) so it's ready to charge.
- A README covering setup, environment variables, and how to deploy.

Ship a working MVP I can run locally first, then help me deploy it.