docs: add comprehensive documentation and deployment guide

[leoneperdigao]

Description

Create comprehensive project documentation covering everything from quick start to production deployment. Good documentation lowers the barrier to adoption and contribution, making it easier for organizations to evaluate and deploy the tracker.

Tasks

• Write README with:
  • Feature overview and value proposition
  • Screenshots of key dashboard views
  • Quick start guide (Docker Compose one-liner)
  • Technology stack summary
• Create deployment guide:
  • Docker Compose (development)
  • Docker Compose (production with TLS)
  • Kubernetes with Helm chart
  • Cloud deployment (AWS ECS/Fargate, GCP Cloud Run)
• Write API documentation:
  • Authentication guide
  • Endpoint reference with request/response examples
  • Pagination and filtering patterns
  • Webhook payload documentation
• Add contributing guide:
  • Development setup instructions
  • Code style and linting rules
  • PR process and review guidelines
  • Issue and commit message conventions
• Write Architecture Decision Records (ADRs):
  • ADR-001: Monorepo vs. polyrepo
  • ADR-002: Scoring algorithm design
  • ADR-003: Database schema versioning strategy
  • ADR-004: API authentication approach
• Add CHANGELOG following Keep a Changelog format

References

• Keep a Changelog
• ADR specification