feat: record who created join codes and who added each node [CI]

backend/openapi/v1.json

@@ -4812,6 +4812,12 @@
           "ipv6_host_auto": {
             "type": "boolean",
             "default": true
+          },
+          "added_by": {
+            "type": [
+              "null",
+              "string"
+            ]
           }
         }
       },
@@ -6204,6 +6210,12 @@
           "role": {
             "type": "string",
             "default": "agent"
+          },
+          "created_by": {
+            "type": [
+              "null",
+              "string"
+            ]
           }
         }
       },
@@ -7721,6 +7733,12 @@
                 "$ref": "#/components/schemas/Ipv6DiagnosticDto"
               }
             ]
+          },
+          "added_by": {
+            "type": [
+              "null",
+              "string"
+            ]
           }
         }
       },