fix: correct pve1 IP to 10.42.0.4, rename stale joel/opnsense refs

pve1 is a static/DHCP-reserved Proxmox host at 10.42.0.4 (previously
mislabeled 'joel' in some places). 10.42.1.1 is the UDM Pro gateway
IP, not pve1 -- OPNsense was retired in favor of Ubiquiti. Removes
the stale duplicate PVE1 DHCP reservation at 10.42.1.1 and drops the
now-redundant 'joel' entry from network.json (consolidated into
pve1).

hosts/unstable/genesis/networking/dhcp.nix

@@ -60,7 +60,7 @@
         reservations = [
           # Static IPs for personal work
           {
-            hw-address = "00:23:24:72:64:32"; # Joel
+            hw-address = "00:23:24:72:64:32"; # PVE1
             ip-address = "10.42.0.4";
           }
           {
@@ -76,10 +76,6 @@
             #ip-address = "10.42.2.253";
             ip-address = "10.42.100.6";
           }
-          {
-            hw-address = "7c:83:34:b9:ee:ec"; # PVE1
-            ip-address = "10.42.1.1";
-          }
           {
             hw-address = "74:ee:2a:66:b3:51"; # printer
             ip-address = "10.42.1.3";