feat: Implement multi-database architecture

This commit introduces a three-database architecture to the application,
as specified in the `db_logic.md` file.

The changes include:
- A SQL initialization script (`db/init/init.sql`) to create the
  `USERS_ALMA`, `vanity_hr`, and `vanity_attendance` databases and their
  respective tables.
- SQLAlchemy models for all tables, organized into separate files
  within the `models` directory.
- Refactoring of the database connection logic in `modules/database.py`
  to support connections to all three databases.
- Creation of a `modules/logger.py` to handle request logging to the
  `USERS_ALMA` database.
- Updates to `docker-compose.yml` to mount the initialization script and
  build the bot image locally.
- Updates to `.env.example` to include the new database environment
  variables.
- Restoration of the data dictionary to `db_tasks.md`.

main.py

@@ -18,7 +18,8 @@ from telegram.ext import Application, Defaults, CommandHandler, ContextTypes
 # --- IMPORTAR HABILIDADES ---
 from modules.onboarding import onboarding_handler
 from modules.rh_requests import vacaciones_handler, permiso_handler
-from modules.database import log_request, chat_id_exists # Importar chat_id_exists
+from modules.logger import log_request
+from modules.database import chat_id_exists # Importar chat_id_exists
 from modules.ui import main_actions_keyboard
 # from modules.finder import finder_handler (Si lo creas después)