Refactor to modular production-ready Express + TypeScript starter with CI, Docker and tests

[mirrrjr]

Motivation

• Move from a minimal example to a production-minded, modular architecture with clear separation of concerns (config, infra, modules, shared middleware, and typed services/repositories).
• Add operational primitives required for running in real environments: structured logging, environment validation, health/readiness, graceful shutdown, rate limiting, CORS/security headers, and Docker support.

Description

• Introduces a modular app factory and bootstrapping: createApp, start with graceful shutdown, and database lifecycle in src/infrastructure/database/mongoose.ts and src/index.ts.
• Implements a typed users feature module with schema/validation, service, controller, repository implementations (MongooseUserRepository and InMemoryUserRepository), password hashing, and request validation under src/modules/users/* and src/shared/* helper middleware and errors.
• Adds environment parsing and logger in src/config/env.ts and src/config/logger.ts, plus middlewares for request IDs, request logging, security headers, rate limiting, not-found and error handling in src/shared/middleware/*.
• Adds health and OpenAPI endpoints in src/modules/health and src/modules/openapi, a test/app.test.ts exercising health and user flows against an in-memory repo, TypeScript config tightening in tsconfig.json, Dockerfile, docker-compose.yml, .dockerignore, GitHub Actions CI (.github/workflows/ci.yml), and README updates; also updates package.json to PNPM tooling and scripts and replaces package-lock.json with pnpm-lock.yaml updates.

Testing

• Ran lint with pnpm lint, the TypeScript checks completed successfully. (CI includes pnpm lint.)
• Ran the test suite with pnpm test which executes the node test runner on test/*.test.ts, and the tests passed locally/CI. (CI workflow runs pnpm test.)
• Built the project with pnpm build, and the build completed successfully; the CI job also runs pnpm build.

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Codex Task