[Feature Request]: Support for CLI-native external MFA.

**Is your feature request related to a problem? Please describe.**
Currently, when utilizing external identity providers (such as Microsoft) for authentication via the DefGuard, the process requires opening a web browser. This creates friction in headless environments, on remote servers, and within terminal-driven workflows.

**Describe the solution you'd like**
Could native support for asynchronous external MFA flows (such as push notifications via Microsoft Authenticator) be implemented directly within the DefGuard?
Since the user is already enrolled and mapped within DefGuard during the initial setup, would it be possible for a VPN connection attempt from the terminal to directly trigger an authentication prompt on the user's registered ms authenticator app, completely bypassing the requirement for an interactive web browser session? (Assuming this is technically feasible with external IdPs).