add @ mentions in chat

frontend/src/lib/stores/chat.svelte.ts

@@ -1,5 +1,6 @@
 import { pb } from '$lib/pocketbase';
-import type { ChatMessage, TypingRow } from '$lib/types';
+import type { ChatMessage, TypingRow, MentionMember } from '$lib/types';
+import { addAutoDismissNotice } from './notices.svelte';
 
 interface ChatInit {
 	famId: string;
@@ -8,7 +9,7 @@ interface ChatInit {
 	actorName: string;
 	actorColor: string;
 	pbToken?: string;
-	
+	members?: MentionMember[];
 }
 
 // Client id for optimistic chat messages. `crypto.randomUUID()` requires a
@@ -34,6 +35,7 @@ class ChatStore {
 	actorName = $state('');
 	actorColor = $state('');
 	pbToken = $state('');
+	members = $state<MentionMember[]>([]);
 
 	private unsubs: (() => void)[] = [];
 	private destroyed = false;
@@ -80,6 +82,7 @@ class ChatStore {
 		this.actorName = opts.actorName;
 		this.actorColor = opts.actorColor;
 		this.pbToken = opts.pbToken || '';
+		this.members = opts.members || [];
 		this.messages = [];
 		this.typing = {};
 		this.unread = 0;
@@ -160,9 +163,24 @@ class ChatStore {
 		if (record.authorId !== this.actorId) {
 			if (!this.open) this.unread++;
 			this.playDunk();
+			this.notifyIfMentioned(record);
 		}
 	}
 
+	// Toast the current user when a message @mentions them by name.
+	private notifyIfMentioned(record: ChatMessage) {
+		const lower = (record.content || '').toLowerCase();
+		const me = this.members.find((m) => m.id === this.actorId);
+		if (!me || !me.name) return;
+		if (!lower.includes('@' + me.name.toLowerCase())) return;
+		addAutoDismissNotice({
+			type: 'info',
+			title: 'You were mentioned 👋',
+			message: `${record.authorName || 'Someone'}: ${record.content}`,
+			dismissible: true
+		});
+	}
+
 	private onTyping(action: string, record: TypingRow) {
 		if (record.famId !== this.famId) return;
 		if (action === 'delete') {
@@ -310,6 +328,7 @@ class ChatStore {
 		for (const t of this.typingTimers.values()) clearTimeout(t);
 		this.typingTimers.clear();
 		this.initialized = false;
+		this.members = [];
 	}
 }