Allow Customization of /migrations Directory in config.toml for Supabase Migrations and Shadow Database

Feature Request Summary Currently, Supabase enforces the /migrations directory as the fixed location for storing SQL schema migration files. This setting is not configurable, and developers cannot change it in config.toml. Additionally, the shadow database—created when running supabase db diff—also strictly uses the /migrations directory, without an option to customize its location. Problem Statement Many development teams have unique project structures and workflows that require flexibility in where migration files are stored. Being forced to use /migrations can cause conflicts in monorepos, CI/CD pipelines, and certain deployment setups. Proposed Solution Introduce an option in config.toml—likely under the [db] section—to allow developers to specify a custom directory for migration files. Example: Benefits • Greater flexibility in project structure. • More control over versioning and organization of database migrations, especially when "diffi…