add more ux and ui patches with extra login helper

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

@@ -40,6 +40,7 @@ class ChatStore {
 	private initPromise: Promise<void> | null = null;
 	private lastSeenAt = 0;
 	private typingTimers = new Map<string, ReturnType<typeof setTimeout>>();
+	private audioCtx: AudioContext | null = null;
 
 	typingNames = $derived.by(() => {
 		const names: string[] = [];
@@ -156,8 +157,9 @@ class ChatStore {
 		}
 		// Stop showing their typing indicator once the message lands.
 		this.clearTyping(record.authorId);
-		if (record.authorId !== this.actorId && !this.open) {
-			this.unread++;
+		if (record.authorId !== this.actorId) {
+			if (!this.open) this.unread++;
+			this.playDunk();
 		}
 	}
 
@@ -184,6 +186,39 @@ class ChatStore {
 		if (this.typing[actorId]) this.removeTyping(actorId);
 	}
 
+	// Short, low-volume "dunk" blip played when a message from someone else is
+	// broadcast in. Synthesised with the Web Audio API so there's no asset to
+	// ship. Browsers require a user gesture before audio can start, but chat
+	// messages only arrive after the user has interacted, so the context
+	// resumes fine. Failures are silently ignored.
+	private playDunk() {
+		if (typeof window === 'undefined' || typeof AudioContext === 'undefined') return;
+		try {
+			const Ctor = window.AudioContext || (window as any).webkitAudioContext;
+			if (!Ctor) return;
+			if (!this.audioCtx) this.audioCtx = new Ctor();
+			const ctx = this.audioCtx;
+			if (ctx.state === 'suspended') ctx.resume();
+
+			const now = ctx.currentTime;
+			const osc = ctx.createOscillator();
+			const gain = ctx.createGain();
+			osc.type = 'sine';
+			// Quick downward pitch sweep gives the soft "dun-nk" thud.
+			osc.frequency.setValueAtTime(190, now);
+			osc.frequency.exponentialRampToValueAtTime(70, now + 0.18);
+			// Low volume with a fast attack/decay envelope.
+			gain.gain.setValueAtTime(0.0001, now);
+			gain.gain.exponentialRampToValueAtTime(0.12, now + 0.01);
+			gain.gain.exponentialRampToValueAtTime(0.0001, now + 0.22);
+			osc.connect(gain).connect(ctx.destination);
+			osc.start(now);
+			osc.stop(now + 0.24);
+		} catch {
+			/* audio is best-effort */
+		}
+	}
+
 	private removeTyping(actorId: string) {
 		if (!this.typing[actorId]) return;
 		const next = { ...this.typing };