Use new welshman membership helpers

src/app/components/RoomChat.svelte

@@ -10,7 +10,7 @@
   import type {Maybe} from "@welshman/lib"
   import type {TrustedEvent, EventContent} from "@welshman/util"
   import {makeEvent, MESSAGE, RELAY_ADD_MEMBER, ROOM_ADD_MEMBER} from "@welshman/util"
-  import {publish} from "@welshman/app"
+  import {MembershipStatus, publish} from "@welshman/app"
   import AltArrowDown from "@assets/icons/alt-arrow-down.svg?dataurl"
   import ClockCircle from "@assets/icons/clock-circle.svg?dataurl"
   import Login2 from "@assets/icons/login-3.svg?dataurl"
@@ -37,7 +37,6 @@
     PROTECTED,
     RoomType,
     deriveUserRoomMembershipStatus,
-    MembershipStatus,
     getRoomType,
     prependParent,
   } from "@app/rooms"

src/app/components/RoomDetailMenu.svelte

@@ -2,7 +2,7 @@
   import {onMount} from "svelte"
   import {goto} from "$app/navigation"
   import type {Command} from "@welshman/app"
-  import {publish} from "@welshman/app"
+  import {MembershipStatus, publish} from "@welshman/app"
   import Pen from "@assets/icons/pen.svg?dataurl"
   import TrashBin2 from "@assets/icons/trash-bin-2.svg?dataurl"
   import Login3 from "@assets/icons/login-3.svg?dataurl"
@@ -13,7 +13,7 @@
   import Confirm from "@lib/components/Confirm.svelte"
   import RoomEdit from "@app/components/RoomEdit.svelte"
   import {app, roomLists, rooms} from "@app/core"
-  import {deriveUserIsRoomAdmin, deriveUserRoomMembershipStatus, MembershipStatus} from "@app/rooms"
+  import {deriveUserIsRoomAdmin, deriveUserRoomMembershipStatus} from "@app/rooms"
   import {makeSpacePath} from "@app/routes"
   import {pushModal} from "@app/modal"
   import {pushToast} from "@app/toast"

src/app/rooms.ts

@@ -2,20 +2,9 @@ import * as nip19 from "nostr-tools/nip19"
 import {derived} from "svelte/store"
 import {sortBy, uniq} from "@welshman/lib"
 import type {Maybe} from "@welshman/lib"
-import {
-  MESSAGE,
-  ROOM_ADD_MEMBER,
-  ROOM_JOIN,
-  ROOM_LEAVE,
-  ROOM_REMOVE_MEMBER,
-  makeEvent,
-  outbox,
-  seen,
-  sortEventsAsc,
-  toNostrURI,
-} from "@welshman/util"
+import {MESSAGE, makeEvent, outbox, seen, toNostrURI} from "@welshman/util"
 import type {EventContent, TrustedEvent} from "@welshman/util"
-import {RoomLists, makeRoomKey, createSearch} from "@welshman/app"
+import {MembershipStatus, RoomLists, makeRoomKey, createSearch} from "@welshman/app"
 import type {Room, RoomMeta} from "@welshman/app"
 import {
   deriveUserItem,
@@ -29,15 +18,8 @@ import {
   user,
 } from "@app/core"
 import {deriveUserIsSpaceAdmin} from "@app/management"
-import {deriveEventsForUrl} from "@app/repository"
 import {makeRoomPath} from "@app/routes"
 
-export enum MembershipStatus {
-  Initial,
-  Pending,
-  Granted,
-}
-
 export const ROOM = "h"
 
 export const PROTECTED = ["-"]
@@ -58,7 +40,7 @@ export const displayRoom = (url: string, h: string) =>
 export const roomComparator = (url: string) => (h: string) => displayRoom(url, h).toLowerCase()
 
 export const deriveRoomMembers = (url: string, h: string) =>
-  derived(rooms.get().forRoom(url, h), $room => $room?.members?.members() ?? [])
+  derived(rooms.get().members(url, h).$, $members => Array.from($members))
 
 // A room member also has to be allowed at the relay level, or they won't be able to read the
 // room at all.
@@ -181,44 +163,11 @@ export const deriveUserIsRoomAdmin = (url: string, h: string) =>
       $isSpaceAdmin || Boolean($room?.admins?.pubkeys().includes($user.pubkey)),
   )
 
+// Room membership is the relay's business, but a space admin outranks it.
 export const deriveUserRoomMembershipStatus = (url: string, h: string) =>
   derived(
-    [
-      user,
-      rooms.get().forRoom(url, h),
-      deriveEventsForUrl(url, [{kinds: [ROOM_ADD_MEMBER, ROOM_REMOVE_MEMBER], "#h": [h]}]),
-      deriveEventsForUrl(url, [{kinds: [ROOM_JOIN, ROOM_LEAVE], "#h": [h]}]),
-      deriveUserIsRoomAdmin(url, h),
-    ],
-    ([$user, $room, $addRemoveEvents, $joinLeaveEvents, $isAdmin]) => {
-      if ($isAdmin) {
-        return MembershipStatus.Granted
-      }
-
-      let isMember = false
-
-      if ($room?.members) {
-        isMember = $room.members.isMember($user.pubkey)
-      } else {
-        for (const event of sortEventsAsc($addRemoveEvents)) {
-          if (event.pubkey === $user.pubkey) {
-            isMember = event.kind === ROOM_ADD_MEMBER
-          }
-        }
-      }
-
-      for (const event of $joinLeaveEvents) {
-        if (event.pubkey === $user.pubkey) {
-          if (event.kind === ROOM_JOIN) {
-            return isMember ? MembershipStatus.Granted : MembershipStatus.Pending
-          }
-
-          return MembershipStatus.Initial
-        }
-      }
-
-      return isMember ? MembershipStatus.Granted : MembershipStatus.Initial
-    },
+    [rooms.get().membershipStatus(url, h).$, deriveUserIsRoomAdmin(url, h)],
+    ([$status, $isAdmin]) => ($isAdmin ? MembershipStatus.Granted : $status),
   )
 
 export const deriveUserRoomSearch = () =>