feat: profile page, admin pages, infinite scroll on browse

- Add /profile page with reading settings (voice, speed, auto-next) and password change form
- Add /admin/scrape page showing scraping task history with live status polling and trigger controls
- Add /admin/audio page showing audio cache entries with client-side search filter
- Add changePassword(), listAudioCache(), listScrapingTasks() to pocketbase.ts
- Add /api/admin/scrape and /api/browse-page server-side proxy routes
- Replace browse page pagination with IntersectionObserver infinite scroll
- Update nav: username becomes a /profile link; admin users see Scrape and Audio cache links

ui/src/routes/admin/scrape/+page.server.ts

@@ -0,0 +1,29 @@
+import { redirect } from '@sveltejs/kit';
+import type { PageServerLoad } from './$types';
+import { listScrapingTasks } from '$lib/server/pocketbase';
+import { env } from '$env/dynamic/private';
+import { log } from '$lib/server/logger';
+
+const SCRAPER_URL = env.SCRAPER_API_URL ?? 'http://localhost:8080';
+
+export const load: PageServerLoad = async ({ locals }) => {
+	if (locals.user?.role !== 'admin') {
+		redirect(302, '/');
+	}
+
+	const [tasks, statusRes] = await Promise.all([
+		listScrapingTasks().catch((e) => {
+			log.warn('admin/scrape', 'failed to load tasks', { err: String(e) });
+			return [];
+		}),
+		fetch(`${SCRAPER_URL}/api/scrape/status`).catch(() => null)
+	]);
+
+	let running = false;
+	if (statusRes?.ok) {
+		const body = await statusRes.json().catch(() => null);
+		running = body?.running ?? false;
+	}
+
+	return { tasks, running };
+};