claude@clouddev1
3dbaedc1da
ADR-0017 added --force-conversion / --dont-convert as opt-in flags on `change column`; the help text already mentioned the flags but didn't explain when they apply. ADR-0018 generalised serial beyond PK and added auto-fill on `add column ... (serial|shortid)` for non-empty tables; none of that was reflected in user-visible help. This commit: - Annotates the `add column` line with a continuation note that adding serial/shortid to a non-empty table auto-fills existing rows. - Annotates the `change column` line with a continuation note that converting to serial/shortid auto-fills null cells. - Appends an "Auto-generated types" section explaining serial and shortid: how they auto-fill, that they imply UNIQUE outside a PK (serial) or always (shortid), and that adding/converting-to either type on a non-empty table auto-fills existing/null cells. The new test `help_describes_auto_generated_type_behaviour` pins these phrases so a future help-text edit can't silently drop the pedagogical lines. The existing `help_command_lists_supported_commands` and `help_lists_export_and_import` tests still pass — they only assert substring presence. No engine vocabulary leaks (ADR-0002 posture preserved). 536 -> 537 passing, clippy clean.