[Improvement][API] Add missing critical endpoints for functional verification

[GGWPVV]

Currently, there are no API endpoints for performing key management operations on containers and databases.
These actions are only available via the UI, which prevents backend validation and API-level automation of critical functionality.

Specifically, the following operations cannot be performed through the API:

1. Creating or deleting Docker containers
2. Get Container's List.
3. Creating a database backup
4. Restoring a database from a backup
5. Retrieving a backup link for an existing database