feat(ui): persist user settings and audio position across sessions

- Replace double inline player controls with compact 'now playing' indicator when mini-bar is active
- Add user_settings PocketBase collection (auto_next, voice, speed) and audio_time field on progress
- Add getSettings/saveSettings/setAudioTime/getAudioTime server functions
- Add GET/PUT /api/settings and GET/PATCH /api/progress/audio-time API routes
- Load settings server-side in layout and apply to audioStore on mount
- Debounced 800ms effect persists settings changes to DB
- Save audio currentTime on pause/end; restore position when replaying a chapter

ui/src/routes/api/settings/+server.ts

@@ -0,0 +1,49 @@
+import { json, error } from '@sveltejs/kit';
+import type { RequestHandler } from './$types';
+import { getSettings, saveSettings } from '$lib/server/pocketbase';
+import { log } from '$lib/server/logger';
+
+/**
+ * GET /api/settings
+ * Returns the current user's settings (auto_next, voice, speed).
+ * Returns defaults if no settings record exists yet.
+ */
+export const GET: RequestHandler = async ({ locals }) => {
+	try {
+		const settings = await getSettings(locals.sessionId, locals.user?.id);
+		return json({
+			autoNext: settings?.auto_next ?? false,
+			voice: settings?.voice ?? 'af_bella',
+			speed: settings?.speed ?? 1.0
+		});
+	} catch (e) {
+		log.error('settings', 'GET failed', { err: String(e) });
+		error(500, 'Failed to load settings');
+	}
+};
+
+/**
+ * PUT /api/settings
+ * Body: { autoNext: boolean, voice: string, speed: number }
+ * Saves user preferences.
+ */
+export const PUT: RequestHandler = async ({ request, locals }) => {
+	const body = await request.json().catch(() => null);
+
+	if (
+		!body ||
+		typeof body.autoNext !== 'boolean' ||
+		typeof body.voice !== 'string' ||
+		typeof body.speed !== 'number'
+	) {
+		error(400, 'Invalid body — expected { autoNext, voice, speed }');
+	}
+
+	try {
+		await saveSettings(locals.sessionId, body, locals.user?.id);
+	} catch (e) {
+		log.error('settings', 'PUT failed', { err: String(e) });
+		error(500, 'Failed to save settings');
+	}
+	return json({ ok: true });
+};