feat(library): local lossless index, filters, and conserve dedicated page (#871)

* feat(library): local lossless index, filters, and conserve dedicated page

Add SQLite-backed lossless album browse and advanced-search filtering,
wire All Albums and artist/album lossless drill-down mode, and hide the
standalone /lossless-albums nav entry from sidebar visibility settings
(conserved route, default off).

* docs(release): note lossless local index in CHANGELOG and credits (PR #871)

src/components/LosslessFilterButton.tsx

@@ -0,0 +1,30 @@
+import { Gem } from 'lucide-react';
+import { useTranslation } from 'react-i18next';
+
+interface Props {
+  active: boolean;
+  onChange: (next: boolean) => void;
+}
+
+export default function LosslessFilterButton({ active, onChange }: Props) {
+  const { t } = useTranslation();
+  const tooltip = active ? t('albums.losslessTooltipOn') : t('albums.losslessTooltipOff');
+  const activeStyle = active ? { background: 'var(--accent)', color: 'var(--ctp-crust)' } : {};
+
+  return (
+    <button
+      type="button"
+      className={`btn btn-surface${active ? ' btn-sort-active' : ''}`}
+      onClick={() => onChange(!active)}
+      aria-pressed={active}
+      data-tooltip={tooltip}
+      data-tooltip-pos="bottom"
+      style={{
+        display: 'flex', alignItems: 'center', gap: '0.4rem', ...activeStyle,
+      }}
+    >
+      <Gem size={14} />
+      {t('albums.losslessLabel')}
+    </button>
+  );
+}