implement blog subscription feature with modal and email handling

app/actions/subscribeNewsletter.ts

@@ -0,0 +1,26 @@
+'use server';
+
+import { addContact } from '@/lib/mail';
+
+export type SubscribeState = { success: true } | { success: false; error: string } | null;
+
+export async function subscribeNewsletter(
+    _: SubscribeState,
+    formData: FormData,
+): Promise<SubscribeState> {
+    const email = (formData.get('email') as string)?.trim();
+
+    if (!email) return { success: false, error: "L'adresse email est requise." };
+
+    const emailRe = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
+    if (!emailRe.test(email)) {
+        return { success: false, error: 'Adresse email invalide.' };
+    }
+
+    try {
+        await addContact(email);
+        return { success: true };
+    } catch (err) {
+        return { success: false, error: 'Une erreur est survenue. Réessaie plus tard.' };
+    }
+}