Perform PTR lookups for Persistent Clients

### 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

### Description

#### What problem are you trying to solve?

As a user, I want to see resolved client names in query logs even when those clients match a Persisted Client entry in the Client Settings page.

#### Proposed solution

I propose that PTR / rDNS queries should still take place for *all* clients, even if they match a "Persisted Client" setting in the "Client Settings". The name of the "Persisted Client" entry should instead serve as a fallback name if that rDNS query did not happen or returned no result.

#### Alternatives considered

None.

#### Additional information

My personal use case for persistent clients has nothing to do with rDNS queries. I create persisted clients to represent subnets in my network. In many cases, those subnets are defined by the DNS rules I apply to them. For example, I have a subnet dedicated to my kids devices. For that subnet, I want to be able to block various services in AGH, such as Youtube. By doing so, however, I no longer have useful client names in the Query Logs due to the PTR/rDNS lookups not taking place.

Original discussion: #5737