Rewrite README into comprehensive developer/researcher/deployment guide

[Spbd1]

Motivation

• Provide a professional, complete README so developers, researchers, and deployers can run the local demo, follow the research flow, deploy a pilot server, collect data, and export results.
• Make operational details explicit (routes, server submission flags, env variables, Docker and native deployment) to reduce setup errors and clarify privacy/ethics implications.
• Consolidate implemented behaviour (localStorage-first exports, optional server submission, admin endpoints, CSV/JSON export, computed metrics) into a single authoritative reference.

Description

• Rewrote README.md into a structured guide that documents the study purpose, the full participant route sequence (/, /consent, /background, /game, /visible-results, /pre-reveal-survey, /hidden-rule-reveal, /post-reveal-survey, /individual-results, /export, /admin) and the research rationale (invisible inequality, attribution, fairness, protest legitimacy, redistribution, pre/post reveal design).
• Added implementation and run instructions including stack details (Next.js 14, TypeScript, Tailwind), quick-start commands (npm install, npm run dev), local production checks (npm run typecheck, npm run lint, npm run build, npm run start), and PM2 example for process supervision.
• Documented server pilot deployment with Docker and without Docker (commands such as cp .env.example .env, docker compose up --build -d, docker compose exec app npm run db:migrate, and native steps including npm run db:generate and npm run db:migrate).
• Added operational docs for data collection and admin exports, including the local-first flow (localStorage → optional POST /api/submissions → PostgreSQL → /admin), environment variables table (notably DATABASE_URL, APP_BASE_URL, ENABLE_SERVER_SUBMISSION, NEXT_PUBLIC_ENABLE_SERVER_SUBMISSION, ADMIN_EXPORT_TOKEN, SUBMISSION_RATE_LIMIT_*, MAX_SUBMISSION_BODY_BYTES, CONSENT_VERSION, SCHEMA_VERSION), curl examples for JSON and CSV exports, description of admin endpoints (/api/admin/submissions, /api/admin/submissions.csv, /api/admin/stats), the export:submissions script, data schema, survey measures, computed metrics, privacy/ethics guidance, security notes, troubleshooting, and a development scripts table.

Testing

• Ran git diff --check and repository checks; no whitespace errors were reported.
• Attempted build-time checks (npm run typecheck, npm run lint, npm run build), but these could not complete prior to installing dependencies.
• npm install failed in this environment because the registry returned 403 Forbidden for @prisma/client, so dependency installation and the subsequent TypeScript/Eslint/build checks remain blocked until dependencies can be installed successfully.

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Codex Task