- Introduced a new method `runCustomMigrations` in `DbService` to execute custom SQL statements that Drizzle cannot manage, such as triggers and virtual tables.
- Updated `database-patterns.md` and `README.md` to document the handling of custom SQL and its importance in maintaining database integrity during migrations.
- Refactored `messageFts.ts` to define FTS5 virtual table and associated triggers as idempotent SQL statements for better migration management.
- Revised the README files for shared data and main data layers to improve clarity and structure.
- Consolidated documentation on shared data types and API types, removing the now-deleted `api-design-guidelines.md`.
- Streamlined directory structure descriptions and updated links to relevant documentation.
- Enhanced quick reference sections for better usability and understanding of the data architecture.
