Add a dropdown for resource selection and adopt it in the 'Image' node (#4543)

* Add a dropdown for resource selection and adopt it in the Image node

* Route every image upload through a new ResourceUpload handler with desktop support and migrate wired 'Image' node inputs

* Show each resource's user count in the resource picker dropdown

* Send a picked resource file to the document that requested it, list every non-font resource in the picker, and link sibling message docs

node-graph/graph-craft/src/document/value.rs

@@ -42,6 +42,7 @@ macro_rules! for_each_item_type_default {
 		$action!(Gradient);
 		$action!(Artboard);
 		$action!(String);
+		$action!(Resource);
 	};
 }
 
@@ -63,7 +64,6 @@ macro_rules! for_each_list_type_default {
 macro_rules! for_each_bare_type_default {
 	($action:ident) => {
 		$action!(DocumentNode);
-		$action!(Resource);
 	};
 }