Consolidate all test and development configuration into a single source of truth (.env.dev) for cleaner, more maintainable setup. Changes: - Remove obsolete .env.test and .env.test.example files - Update Makefile to load .env.dev variables automatically via include - Simplify test commands (no more bash subshells or complex sourcing) - Update integration tests to read config from environment variables - Rewrite TESTING_SUMMARY.md with current unified approach - Update LOCAL_DEVELOPMENT.md to reference single config file Benefits: - Single source of truth for all configuration - Simpler test execution: just `make test` - Isolated test DB (port 5434) separate from dev (port 5433) - Better documentation and developer experience 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>