systemd socket activation support

### Prerequisites

- [x] I have checked the [Wiki](https://github.com/AdguardTeam/AdGuardHome/wiki) and [Discussions](https://github.com/AdguardTeam/AdGuardHome/discussions) and found no answer

- [x] I have searched other issues and found no duplicates

- [x] I want to request a feature or enhancement and not ask a question

### The problem

When running Adguard Home with rootless Podman, netavark is used as the network stack. In that case, the container is not able to see the real client IP. To the Adguard container it looks like every request is coming from the same client.

### Proposed solution

One way for a rootless container to see the real client IP would be [systemd socket activation](https://www.freedesktop.org/software/systemd/man/latest/systemd-socket-activate.html). Podman has [support](https://github.com/containers/podman/blob/main/docs/tutorials/socket_activation.md) for it. However, Adguard Home currently does not seem to support socket activation.

### Alternatives considered and additional information

Besides seing the real client ip, this would also allow activation of Adguard on incoming network requests as well as native network performance for rootless containers.