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/routes/page.server.spec.ts

@@ -281,7 +281,7 @@ describe('home page load — reader branch (isReader = !canWrite && !canAnnotate
 		expect(transcriptionCalls).toHaveLength(0);
 	});
 
-	it('calls /api/stats, /api/persons, /api/documents, /api/geschichten for a read-only user', async () => {
+	it('calls /api/stats, /api/persons, /api/documents/search, /api/geschichten for a read-only user', async () => {
 		const mockGet = vi.fn().mockResolvedValue({ response: { ok: true, status: 200 }, data: null });
 		vi.mocked(createApiClient).mockReturnValue({ GET: mockGet } as ReturnType<
 			typeof createApiClient
@@ -298,7 +298,7 @@ describe('home page load — reader branch (isReader = !canWrite && !canAnnotate
 		const calledEndpoints = mockGet.mock.calls.map((c: unknown[]) => c[0] as string);
 		expect(calledEndpoints).toContain('/api/stats');
 		expect(calledEndpoints).toContain('/api/persons');
-		expect(calledEndpoints).toContain('/api/documents');
+		expect(calledEndpoints).toContain('/api/documents/search');
 		expect(calledEndpoints).toContain('/api/geschichten');
 	});