add AI-generated landing page photography (Gemini 3 Pro)

20 images generated via gemini-3-pro-image-preview (Nano Banana Pro):
- Documentary street photography style, British-diverse subjects
- 12 square (1:1), 8 landscape (16:9) matching placeholder aspect ratios
- Replaced all ImagePlaceholder components with LandingImage + next/image
- Images in public/images/landing/, served statically

Pages updated: /, /for/charities, /for/fundraisers, /for/volunteers, /for/organisations
New component: LandingImage (next/image with fill + object-cover)

pledge-now-pay-later/src/app/for/charities/page.tsx

@@ -1,5 +1,5 @@
 import Link from "next/link"
-import { Nav, Footer, BottomCta, ImagePlaceholder } from "../_components"
+import { Nav, Footer, BottomCta, LandingImage } from "../_components"
 
 export default function ForCharitiesPage() {
   return (
@@ -26,7 +26,7 @@ export default function ForCharitiesPage() {
               </Link>
             </div>
           </div>
-          <ImagePlaceholder aspect="square" label="Charity manager reviewing dashboard on laptop at event" />
+          <LandingImage src="/images/landing/08-charities-hero.jpg" alt="Charity manager reviewing dashboard on laptop at mosque fundraising event" aspect="square" />
         </div>
       </section>
 
@@ -49,7 +49,7 @@ export default function ForCharitiesPage() {
         </div>
       </section>
 
-      {/* ── How it works — with image ── */}
+      {/* ── How it works — with images ── */}
       <section className="py-24 px-6">
         <div className="max-w-5xl mx-auto grid md:grid-cols-2 gap-16 items-start">
           <div>
@@ -73,8 +73,8 @@ export default function ForCharitiesPage() {
             </div>
           </div>
           <div className="space-y-6">
-            <ImagePlaceholder aspect="square" label="Mobile pledge form — amount selection" />
-            <ImagePlaceholder aspect="video" label="WhatsApp reminder conversation" />
+            <LandingImage src="/images/landing/09-charities-amount-selection.jpg" alt="Hand holding phone at charity dinner table showing pledge amount selection" aspect="square" />
+            <LandingImage src="/images/landing/10-charities-whatsapp.jpg" alt="Woman on sofa viewing WhatsApp pledge reminder conversation" aspect="video" />
           </div>
         </div>
       </section>