Fix kubeconfig-sync issues (#2692)

- Removed `getFreePort` as its use is always a race condition. Change
  all uses of it to retrive the port after listening

- Added `getPortFrom` as a helper function to read a port from a stream

- Remove `Cluster.ownerRef` as it is outdated and no longer needed for 5.0

- Remove `Cluster.enabled`, no longer needed because of above

- Removed `Cluster.init`, moved its contents into `Cluster.constructor`
  as nothing in that function is asyncronous. Currently only being run
  on `main` as a stop gap until `renderer` gets its own version of
  `Cluster`

- Refactored `LensProxy` so as to prevent `pty.node` (a NodeJS
  extension) being included in `webpack.extension.ts`'s run

- Removed the passing around of the proxy port as that can now be
  accessed from an instance of `LensProxy`

- purge ContextHandler's cache on disconnect

Co-authored-by: Sebastian Malton <sebastian@malton.name>

src/common/catalog-entities/kubernetes-cluster.ts

@@ -39,7 +39,10 @@ export class KubernetesCluster extends CatalogEntity<CatalogEntityMetadata, Kube
         onlyVisibleForSource: "local",
         onClick: async () => context.navigate(`/entity/${this.metadata.uid}/settings`)
       },
-      {
+    ];
+
+    if (this.metadata.labels["file"]?.startsWith(ClusterStore.storedKubeConfigFolder)) {
+      context.menuItems.push({
         icon: "delete",
         title: "Delete",
         onlyVisibleForSource: "local",
@@ -47,8 +50,8 @@ export class KubernetesCluster extends CatalogEntity<CatalogEntityMetadata, Kube
         confirm: {
           message: `Remove Kubernetes Cluster "${this.metadata.name} from ${productName}?`
         }
-      },
-    ];
+      });
+    }
 
     if (this.status.phase == "connected") {
       context.menuItems.unshift({