v0.2.1

Changed

• Documentation cleanup: tidied prose and grammar across the README and
  documentation, and rewrote the policy-rule examples around a realistic
  article domain. No changes to the published code.
• Modernized the MongoDB and PostgreSQL example apps to current dependency
  majors (mongoose 8, sequelize 6 / pg 8, @faker-js/faker) and made their CI
  jobs gating.

Full changelog: v0.2.0...v0.2.1