chore: prepare release v1.0.0

feat(security): add automated backups, helmet headers, and security tests

fix: relax rate limits for development environment

docs: add comprehensive project readme

test: add playwright e2e testing suite

feat(frontend): add react ui, german localization, and admin dashboard

feat(backend): add express server, prisma schema, and api logic

ops: add docker infrastructure and environment config

chore: initial project setup and gitignore