feat(dashboard): add reader dashboard components

Adds 5 new components for the permission-gated reader layout:
- ReaderStatsStrip: stat tiles (documents / persons / stories) linking to list pages
- ReaderPersonChips: top-N persons by doc count with avatar + name
- ReaderDraftsModule: blog draft list for BLOG_WRITE users
- ReaderRecentDocs: 5 most-recently-updated docs with Neu/Aktualisiert badge
- ReaderRecentStories: 3 latest published stories with 150-char HTML-stripped excerpt

Each component ships with a vitest-browser spec covering the key assertions.
Avatar color/initials logic is inlined to satisfy $lib/shared → $lib/person
boundary rule.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/lib/shared/dashboard/ReaderStatsStrip.svelte

@@ -0,0 +1,43 @@
+<script lang="ts">
+import * as m from '$lib/paraglide/messages.js';
+
+interface Props {
+	documents: number | null;
+	persons: number | null;
+	stories: number | null;
+}
+
+const { documents, persons, stories }: Props = $props();
+</script>
+
+<div class="hidden gap-4 sm:flex">
+	<a
+		href="/documents"
+		class="flex min-h-[44px] flex-col items-center gap-1 rounded-sm border border-line bg-surface px-5 py-3 shadow-sm transition-colors hover:border-brand-mint focus-visible:ring-2 focus-visible:ring-brand-navy focus-visible:outline-none"
+	>
+		<span class="font-serif text-2xl font-bold text-brand-navy">{documents ?? '—'}</span>
+		<span class="font-sans text-xs tracking-widest text-ink-3 uppercase"
+			>{m.dashboard_reader_stats_documents()}</span
+		>
+	</a>
+
+	<a
+		href="/persons"
+		class="flex min-h-[44px] flex-col items-center gap-1 rounded-sm border border-line bg-surface px-5 py-3 shadow-sm transition-colors hover:border-brand-mint focus-visible:ring-2 focus-visible:ring-brand-navy focus-visible:outline-none"
+	>
+		<span class="font-serif text-2xl font-bold text-brand-navy">{persons ?? '—'}</span>
+		<span class="font-sans text-xs tracking-widest text-ink-3 uppercase"
+			>{m.dashboard_reader_stats_persons()}</span
+		>
+	</a>
+
+	<a
+		href="/geschichten"
+		class="flex min-h-[44px] flex-col items-center gap-1 rounded-sm border border-line bg-surface px-5 py-3 shadow-sm transition-colors hover:border-brand-mint focus-visible:ring-2 focus-visible:ring-brand-navy focus-visible:outline-none"
+	>
+		<span class="font-serif text-2xl font-bold text-brand-navy">{stories ?? '—'}</span>
+		<span class="font-sans text-xs tracking-widest text-ink-3 uppercase"
+			>{m.dashboard_reader_stats_stories()}</span
+		>
+	</a>
+</div>