- Add prisma/schema.prisma with Project/Task models, enums, and relations
- Create src/lib/db.ts singleton Prisma client
- Refactor all 5 API routes to use Prisma queries
- Replace migrate.ts with seed.ts for initial data
- Update Dockerfile for Prisma lifecycle (copy generated client)
- Update tsconfig.json with @/generated/* path alias
- Remove pg and @types/pg dependencies
- Add prisma.config.ts for Prisma 6 config
- Update .gitignore for generated Prisma client
- Migrate due_date/next_occurrence columns from TIMESTAMPTZ to DATE
- Update serializeRow() to distinguish DATE vs TIMESTAMPTZ serialization
- Simplify frontend date parsing (no more timezone workarounds)
- Add Vitest + Testing Library test infrastructure
- Add initial date parsing/formatting unit tests
- Update package.json with dev dependencies (vitest, testing-library, jsdom)
