Support models metadata in node properties (#2754)

browser_tests/assets/missing_models_from_node_properties.json

@@ -0,0 +1,49 @@
+{
+  "last_node_id": 1,
+  "last_link_id": 1,
+  "nodes": [
+    {
+      "id": 1,
+      "type": "CheckpointLoaderSimple",
+      "pos": [256, 256],
+      "size": [315, 98],
+      "flags": {},
+      "order": 0,
+      "mode": 0,
+      "inputs": [],
+      "outputs": [
+        {
+          "name": "MODEL",
+          "type": "MODEL",
+          "links": null
+        },
+        {
+          "name": "CLIP",
+          "type": "CLIP",
+          "links": null
+        },
+        {
+          "name": "VAE",
+          "type": "VAE",
+          "links": null
+        }
+      ],
+      "properties": {
+        "Node name for S&R": "CheckpointLoaderSimple",
+        "models": [
+          {
+            "name": "fake_model.safetensors",
+            "url": "http://localhost:8188/api/devtools/fake_model.safetensors",
+            "directory": "text_encoders"
+          }
+        ]
+      },
+      "widgets_values": ["fake_model.safetensors"]
+    }
+  ],
+  "links": [],
+  "groups": [],
+  "config": {},
+  "extra": {},
+  "version": 0.4
+}