Add relay members list and room join/leave events

src/app/components/ChannelItemAddMember.svelte

@@ -0,0 +1,18 @@
+<script lang="ts">
+  import type {TrustedEvent} from "@welshman/util"
+  import {getPubkeyTagValues} from "@welshman/util"
+  import ProfileLink from "@app/components/ProfileLink.svelte"
+
+  type Props = {
+    url: string
+    event: TrustedEvent
+  }
+
+  const {url, event}: Props = $props()
+</script>
+
+{#each getPubkeyTagValues(event.tags) as pubkey}
+  <div class="py-1 text-center text-xs opacity-75">
+    <ProfileLink unstyled class="text-primary" {url} {pubkey} /> joined the room
+  </div>
+{/each}