Generate cover image (#376)

* Make mutating metadata ops mutation
* Implement scene generate screenshot
* Remove fetch policy on metadata mutations
* Port UI changes to v2.5
* Set generated image in database

ui/v2.5/src/components/Scenes/SceneDetails/Scene.tsx

@@ -14,6 +14,7 @@ import { SceneFileInfoPanel } from "./SceneFileInfoPanel";
 import { SceneEditPanel } from "./SceneEditPanel";
 import { SceneDetailPanel } from "./SceneDetailPanel";
 import { OCounterButton } from "./OCounterButton";
+import { SceneOperationsPanel } from "./SceneOperationsPanel";
 
 export const Scene: React.FC = () => {
   const { id = "new" } = useParams();
@@ -144,6 +145,11 @@ export const Scene: React.FC = () => {
               onDelete={() => history.push("/scenes")}
             />
           </Tab>
+          <Tab eventKey="scene-operations-panel" title="Operations">
+            <SceneOperationsPanel 
+              scene={scene} 
+            />
+          </Tab>
         </Tabs>
       </div>
     </>