Update event date to 24 april, add venue, add Ichtus Antwerpen as co-sponsor

- Change event date from 18 to 24 april across all pages, hero, meta and constants
- Add venue (Lange Winkelstraat 5, 2000 Antwerpen) to contact page, Q&A, and transactional emails
- Add LOCATION constant to packages/api/src/constants.ts
- Add Ichtus Antwerpen (ichtusantwerpen.com) as co-sponsor in footer and contact page
- Add location info card to confirmation, update, payment reminder and payment confirmation emails

apps/web/src/components/homepage/Footer.tsx

@@ -86,6 +86,26 @@ export default function Footer() {
 					{/* Vertical rule */}
 					<div className="hidden h-28 w-px bg-white/20 md:block" />
 
+					{/* Ichtus Antwerpen */}
+					<a
+						href="https://ichtusantwerpen.com"
+						target="_blank"
+						rel="noopener noreferrer"
+						className="flex flex-col items-center gap-3 opacity-90 transition-opacity hover:opacity-100"
+					>
+						<img
+							src="/assets/ichtusantwerpen.png"
+							alt="Ichtus Antwerpen"
+							className="h-14 w-auto"
+						/>
+						<p className="text-center font-['DM_Sans',sans-serif] font-medium text-white/60 text-xs uppercase tracking-[0.15em]">
+							Ichtus Antwerpen
+						</p>
+					</a>
+
+					{/* Vertical rule */}
+					<div className="hidden h-28 w-px bg-white/20 md:block" />
+
 					{/* Vlaanderen */}
 					<a
 						href="https://www.vlaanderen.be/cjm/nl"