And the uplink holders' capabilities return

The same split lost them the other way round: the merge base held both changes, each branch had reset
the other's files, and the three-way merge kept neither. Both halves of hq ADR 0161 are on main again
with this.

modules/dhcpcd/module.json

@@ -3,7 +3,8 @@
   "version": "1",
   "capabilities": [
     "package-manager",
-    "service-manager"
+    "service-manager",
+    "uplink-dhcpcd"
   ],
   "claims": [
     {

modules/networkmanager/module.json

@@ -3,7 +3,8 @@
   "version": "1",
   "capabilities": [
     "package-manager",
-    "service-manager"
+    "service-manager",
+    "uplink-networkmanager"
   ],
   "claims": [
     {

modules/systemd-networkd/module.json

@@ -3,7 +3,8 @@
   "version": "1",
   "capabilities": [
     "package-manager",
-    "service-manager"
+    "service-manager",
+    "uplink-systemd-networkd"
   ],
   "claims": [
     {