feat(web/m7-363): per-route svelte:head titles for static routes

Add browser tab titles to all 18 static page routes using the pageTitle()
helper from $lib/branding. Titles follow the Minstrel · Section format.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/routes/playlists/+page.svelte

@@ -1,4 +1,5 @@
 <script lang="ts">
+  import { pageTitle } from '$lib/branding';
   import { goto } from '$app/navigation';
   import { Plus } from 'lucide-svelte';
   import PlaylistCard from '$lib/components/PlaylistCard.svelte';
@@ -37,6 +38,8 @@
   }
 </script>
 
+<svelte:head><title>{pageTitle('Playlists')}</title></svelte:head>
+
 <div class="mx-auto max-w-6xl px-4 py-6">
   <header class="mb-6 flex items-center justify-between">
     <h1 class="text-2xl font-medium text-text-primary">Playlists</h1>