Logs logs logs, make logs easier to read & check logs in critical places

[t-aleksander]

• [x] Some logs are difficult to read due to the amount of information or their volume. Notable examples are:

INFO defguard::grpc::gateway: Saved WireGuard peer stats to db: WireguardPeerStats { id: Some(14202), device_id: 2, collected_at: 2024-07-08T12:08:39.743877153, network: 1, endpoint: Some("[redacted]"), upload: 924093312, download: 503682808, latest_handshake: 2024-07-08T11:40:52, allowed_ips: Some("[redacted]") }

And one of the info logs in wireguard-rs.

• [x] Check if there are appropriate logs when core connects / disconnets from proxy (proxy is down & up again).
• [x] Check if there are appropriate logs when gateway connects / disconnets from core (core is down & up again).
• [x] Same for starting/braking/finishing enrollment (client <-> proxy <-> core) - logs in client and proxy if correspond to what is going on (eg. scenario can't connect to instance URL - no internet, etc.)