Creates ONE new SQLite schema migration file under packages/core/src/infrastructure/persistence/migrations/, following shep's exact migration conventions (timestamped filename, up() function, idempotent ALTER TABLE with safe defaults).
$curl -o .claude/agents/shep-migration-creator.md https://raw.githubusercontent.com/shep-ai/shep/HEAD/.claude/agents/shep-migration-creator.mdInstalls into the current project.
Install shep-migration-creator by running `curl -o .claude/agents/shep-migration-creator.md https://raw.githubusercontent.com/shep-ai/shep/HEAD/.claude/agents/shep-migration-creator.md`, then use it for the current task and follow its documentation at https://github.com/shep-ai/shep.