Testing

This covers the testing workflow for a SQL database project that's migrating from TCL tests to a newer `.sqltest` format. You get specifics on when to use each test type (SQL compatibility tests, Rust integration tests, fuzz tests), how to run them with make commands or cargo, and concrete examples of the `.sqltest` syntax with its pipe-delimited output format. The conversion process is particularly detailed since you'll need to use a converter tool, manually fix warnings, then verify against generated databases with different seeds. The honest reality here is that test migration is messy work involving a lot of manual verification, but the guide at least tells you exactly which commands to run and where files should live.