- Replaced references to `api.settings` with `api.etichette`, `api.flags`, and `api.strings` in various admin pages to align with new API structure.
- Removed the deprecated `settingsRouter` and introduced `flagsRouter`, `etichetteRouter`, and `stringsRouter` to handle respective functionalities.
- Updated the `Flags` schema to change the `value` field from string to boolean.
- Modified flag handling logic in the `SendMessage` and `NewMail` functions to check for boolean flags instead of string values.
- Added migration script to convert the `value` column in the `flags` table from string to boolean.
- Implemented new routers for banners, etichette, flags, revalidation, and strings to encapsulate related functionalities.
