feat(web/m7-363): per-route svelte:head titles for dynamic detail pages

web/src/routes/playlists/[id]/+page.svelte

@@ -1,6 +1,7 @@
 <script lang="ts">
   import { page } from '$app/state';
   import { goto } from '$app/navigation';
+  import { pageTitle } from '$lib/branding';
   import { Pencil, Trash2 } from 'lucide-svelte';
   import { useQueryClient } from '@tanstack/svelte-query';
   import PlaylistTrackRow from '$lib/components/PlaylistTrackRow.svelte';
@@ -136,6 +137,10 @@
   }
 </script>
 
+<svelte:head>
+  <title>{pageTitle(playlistQuery?.data?.name ? `Playlists · ${playlistQuery.data.name}` : 'Playlists')}</title>
+</svelte:head>
+
 <div class="mx-auto max-w-4xl px-4 py-6">
   {#if playlistQuery?.isPending}
     <p class="text-text-muted">Loading…</p>