Fix build error: Force dynamic rendering for calculator page

The calculator page was failing during build because useSearchParams()
requires a request context and cannot be used during static site generation.

Added 'export const dynamic = force-dynamic' to force dynamic rendering,
which allows useSearchParams() to work correctly for QR code parameter detection.

This fixes the build error:
"Error occurred prerendering page "/calculator""

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/calculator/page.tsx

@@ -1,6 +1,9 @@
 import type { Metadata } from 'next';
 import { CalculatorClient } from '../../components/CalculatorClient';
 
+// Force dynamic rendering since we need to read URL search parameters
+export const dynamic = 'force-dynamic';
+
 export const metadata: Metadata = {
   title: 'Carbon Calculator',
   description: 'Calculate your yacht\'s carbon footprint and purchase verified carbon offsets. Enter fuel usage or nautical miles to get accurate CO2 emissions calculations and offset options.',