refactor: rename daemon binary from owlry-core to owlryd

- Binary: owlry-core → owlryd
- Systemd: owlry-core.service → owlryd.service, owlry-core.socket → owlryd.socket
- Client: systemctl start owlryd
- AUR package name stays owlry-core (installs owlryd binary)

systemd/owlryd.service

@@ -5,7 +5,7 @@ After=graphical-session.target
 
 [Service]
 Type=simple
-ExecStart=/usr/bin/owlry-core
+ExecStart=/usr/bin/owlryd
 Restart=on-failure
 RestartSec=3
 Environment=RUST_LOG=warn