docs: full ToC, advanced topics, troubleshooting, usage checklist; ch…

[itriedcoding]

…ore: fix composer deps, add phpstan script; contributing: quickstart and stan

Summary

This PR introduces or updates Sparkify (advanced PHP framework) and the Sparkify Next.js (TypeScript) frontend, with full dev tooling and Docker support.

Changes

• Sparkify framework with DI, routing, middleware (errors, CORS, JSON, request ID, request logging), logging, env/config, console, Doctrine DBAL
• API endpoints: /api/health, /api/v1/hello/{name}
• Next.js 14 app (TypeScript, Tailwind, App Router) proxying /api/* to Sparkify
• Dockerfiles and docker-compose for one-command local dev
• PHPUnit setup and a starter test
• Linting/config: EditorConfig, ESLint (web), PHP CS Fixer (php), GitHub Actions CI

How to test

1. Docker
   • docker compose up --build
   • Visit http://localhost:3000 (frontend) and http://localhost:8000/api/health (backend)
2. Local
   • Backend: cd coreon && composer install && composer run start
   • Frontend: cd web && npm install && npm run dev

Screenshots

N/A

Checklist

• Verified Next.js builds (npm run build)
• Verified API health returns 200
• Lint/typecheck pass for web
• Tests pass (phpunit)