Convert to simple relay-based groups from nip29

src/app/components/SpaceExit.svelte

@@ -1,14 +1,12 @@
 <script lang="ts">
   import {goto} from "$app/navigation"
+  import {displayRelayUrl} from "@welshman/util"
   import Spinner from "@lib/components/Spinner.svelte"
   import Button from "@lib/components/Button.svelte"
   import Icon from "@lib/components/Icon.svelte"
-  import {deriveGroup} from "@app/state"
-  import {removeGroupMemberships} from "@app/commands"
+  import {removeSpaceMembership} from "@app/commands"
 
-  export let nom
-
-  const group = deriveGroup(nom)
+  export let url
 
   const back = () => history.back()
 
@@ -16,7 +14,7 @@
     loading = true
 
     try {
-      await removeGroupMemberships([nom])
+      await removeSpaceMembership(url)
     } finally {
       loading = false
     }
@@ -29,7 +27,7 @@
 
 <form class="column gap-4" on:submit|preventDefault={exit}>
   <h1 class="heading">
-    You are leaving <span class="text-primary">{$group?.name || "[no name]"}</span>
+    You are leaving <span class="text-primary">{displayRelayUrl(url)}</span>
   </h1>
   <p class="text-center">Are you sure you want to leave?</p>
   <div class="flex flex-row items-center justify-between gap-4">