feat: Add book ratings and reviews managed via Directus CMS

Adds a new "Read Books" section below "Currently Reading" in the About
page. Book reviews with star ratings and comments are fetched from a
Directus CMS collection (book_reviews) and displayed with the existing
liquid design system. Includes i18n support (EN/DE), show more/less
toggle, and graceful fallback when the CMS collection does not exist yet.

https://claude.ai/code/session_017E8W9CcHFM5WQVHw74JP34

app/api/book-reviews/route.ts

@@ -0,0 +1,45 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { getBookReviews } from '@/lib/directus';
+
+export const runtime = 'nodejs';
+export const dynamic = 'force-dynamic';
+
+/**
+ * GET /api/book-reviews
+ *
+ * Loads Book Reviews from Directus CMS
+ *
+ * Query params:
+ *   - locale: en or de (default: en)
+ */
+export async function GET(request: NextRequest) {
+  try {
+    const { searchParams } = new URL(request.url);
+    const locale = searchParams.get('locale') || 'en';
+
+    const reviews = await getBookReviews(locale);
+
+    if (reviews && reviews.length > 0) {
+      return NextResponse.json({
+        bookReviews: reviews,
+        source: 'directus'
+      });
+    }
+
+    return NextResponse.json({
+      bookReviews: null,
+      source: 'fallback'
+    });
+
+  } catch (error) {
+    console.error('Error loading book reviews:', error);
+    return NextResponse.json(
+      {
+        bookReviews: null,
+        error: 'Failed to load book reviews',
+        source: 'error'
+      },
+      { status: 500 }
+    );
+  }
+}