Add hCaptcha support alongside Turnstile and reCAPTCHA

- Add hcaptcha_site_key and hcaptcha to captcha_provider options in admin settings
- Update captcha.ts server-side verification for hCaptcha (new endpoint + secret key)
- Add hCaptcha widget rendering in register-form.tsx
- All TypeScript and Biome checks pass

src/app/admin/settings/cms-settings-config.ts

@@ -269,7 +269,7 @@ export const SETTINGS_GROUPS: SettingsGroup[] = [
 			{
 				key: "captcha_provider",
 				label: "Captcha provider",
-				description: "none | turnstile | recaptcha",
+				description: "none | turnstile | recaptcha | hcaptcha",
 				type: "text",
 				defaultValue: "none",
 			},
@@ -278,6 +278,11 @@ export const SETTINGS_GROUPS: SettingsGroup[] = [
 				label: "Turnstile site key",
 				type: "text",
 			},
+			{
+				key: "hcaptcha_site_key",
+				label: "hCaptcha site key",
+				type: "text",
+			},
 			{
 				key: "recaptcha_site_key",
 				label: "reCAPTCHA site key",

src/components/auth/register-form.tsx

@@ -322,6 +322,9 @@ export function RegisterForm({
 				{showCaptcha && captcha.provider === "recaptcha" && (
 					<div className="g-recaptcha" data-sitekey={captcha.siteKey} />
 				)}
+				{showCaptcha && captcha.provider === "hcaptcha" && (
+					<div className="h-captcha" data-sitekey={captcha.siteKey} />
+				)}
 
 				{/* Submit */}
 				<button

src/lib/services/captcha.ts

@@ -2,8 +2,8 @@ import { siteSettings } from "@/lib/services/site-settings";
 
 /**
  * Server-side CAPTCHA verification, driven by website_settings so staff pick the
- * provider in housekeeping. Supports Cloudflare Turnstile and Google reCAPTCHA
- * (the two AtomCMS offers, mutually exclusive).
+ * provider in housekeeping. Supports Cloudflare Turnstile, Google reCAPTCHA,
+ * and hCaptcha (three AtomCMS offers, mutually exclusive).
  *
  * Behaviour:
  *   - provider "none" (or unset) → fail-open (allow)
@@ -11,12 +11,13 @@ import { siteSettings } from "@/lib/services/site-settings";
  *     API error, or network failure → fail-closed (deny)
  *
  * Settings keys:
- *   captcha_provider   = "turnstile" | "recaptcha" | "none" (default none)
+ *   captcha_provider   = "turnstile" | "recaptcha" | "hcaptcha" | "none" (default none)
  *   turnstile_secret / turnstile_site_key
  *   recaptcha_secret  / recaptcha_site_key
+ *   hcaptcha_secret   / hcaptcha_site_key
  */
 export interface CaptchaConfig {
-	provider: "turnstile" | "recaptcha" | "none";
+	provider: "turnstile" | "recaptcha" | "hcaptcha" | "none";
 	siteKey: string;
 	/** Form field the widget writes the token into. */
 	field: string;
@@ -25,6 +26,7 @@ export interface CaptchaConfig {
 const TURNSTILE_URL =
 	"https://challenges.cloudflare.com/turnstile/v0/siteverify";
 const RECAPTCHA_URL = "https://www.google.com/recaptcha/api/siteverify";
+const HCAPTCHA_URL = "https://hcaptcha.com/siteverify";
 
 /** Public config the register/login pages need to render the widget (no secrets). */
 export async function captchaConfig(): Promise<CaptchaConfig> {
@@ -45,6 +47,13 @@ export async function captchaConfig(): Promise<CaptchaConfig> {
 			field: "g-recaptcha-response",
 		};
 	}
+	if (provider === "hcaptcha") {
+		return {
+			provider: "hcaptcha",
+			siteKey: (await siteSettings.get("hcaptcha_site_key", "")) ?? "",
+			field: "hcaptcha-response",
+		};
+	}
 	return { provider: "none", siteKey: "", field: "" };
 }
 
@@ -58,13 +67,22 @@ export async function verifyCaptcha(
 
 	if (!cfg.siteKey) return false;
 
-	const secretKey =
-		cfg.provider === "turnstile" ? "turnstile_secret" : "recaptcha_secret";
+	const secretKey: string =
+		cfg.provider === "turnstile"
+			? "turnstile_secret"
+			: cfg.provider === "recaptcha"
+				? "recaptcha_secret"
+				: "hcaptcha_secret";
 	const secret = (await siteSettings.get(secretKey, "")) ?? "";
 	if (!secret) return false;
 	if (!token) return false;
 
-	const url = cfg.provider === "turnstile" ? TURNSTILE_URL : RECAPTCHA_URL;
+	const url: string =
+		cfg.provider === "turnstile"
+			? TURNSTILE_URL
+			: cfg.provider === "recaptcha"
+				? RECAPTCHA_URL
+				: HCAPTCHA_URL;
 	const body = new URLSearchParams({ secret, response: token });
 	if (remoteIp) body.set("remoteip", remoteIp);