Add public REST API, anti-abuse protections, radio/GitHub cron jobs

Phase A — Public REST API (was the biggest gap). 20 JSON endpoints under
/api mirroring AtomCMS: users/[username], online(+/count), me, articles
(+/[slug]), photos, home, staff, teams, leaderboard, shop(+/categories),
values(+/categories), settings, radio/{config,now-playing,listeners,
shouts}. Shared src/lib/api.ts (apiJson — BigInt-safe + CORS, pagination).
Read-only, fail-soft, and field-safe (never exposes password/auth_ticket/
2FA secrets/mail).

Phase B — Anti-abuse on registration: CAPTCHA (Cloudflare Turnstile /
Google reCAPTCHA, settings-driven, widget rendered on the register page),
VPN/proxy detection (proxycheck.io / IPQualityScore via /admin/vpn
settings), and max-accounts-per-IP. All fail-open when unconfigured.
src/lib/services/{captcha,ip-lookup}.ts.

Phase C — jobs-worker cron suite: radio-record-songs (30s, logs track
changes to radio_song_plays), radio-auto-dj (rotates radio_auto_dj_playlist
when no live DJ), github-update-check (hourly, sets update_available).
Shared src/lib/services/radio.ts (now-playing/listeners parsing).

Verified live (prod, amx_test): /api/* return real JSON (leaderboard 6
users, settings carry no secrets, user endpoint hides password). tsc 0,
vitest 49/49, next build 0 (20 new API routes).

src/lib/services/captcha.ts

@@ -0,0 +1,76 @@
+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). FAIL-OPEN by configuration: when
+ * no provider/secret is set, registration isn't blocked; only an explicitly
+ * configured provider with a failing/absent token blocks.
+ *
+ * Settings keys:
+ *   captcha_provider   = "turnstile" | "recaptcha" | "none" (default none)
+ *   turnstile_secret / turnstile_site_key
+ *   recaptcha_secret  / recaptcha_site_key
+ */
+export interface CaptchaConfig {
+  provider: "turnstile" | "recaptcha" | "none";
+  siteKey: string;
+  /** Form field the widget writes the token into. */
+  field: string;
+}
+
+const TURNSTILE_URL = "https://challenges.cloudflare.com/turnstile/v0/siteverify";
+const RECAPTCHA_URL = "https://www.google.com/recaptcha/api/siteverify";
+
+/** Public config the register page needs to render the widget (no secrets). */
+export async function captchaConfig(): Promise<CaptchaConfig> {
+  const provider = ((await siteSettings.get("captcha_provider", "none")) ?? "none").toLowerCase();
+  if (provider === "turnstile") {
+    return {
+      provider: "turnstile",
+      siteKey: (await siteSettings.get("turnstile_site_key", "")) ?? "",
+      field: "cf-turnstile-response",
+    };
+  }
+  if (provider === "recaptcha") {
+    return {
+      provider: "recaptcha",
+      siteKey: (await siteSettings.get("recaptcha_site_key", "")) ?? "",
+      field: "g-recaptcha-response",
+    };
+  }
+  return { provider: "none", siteKey: "", field: "" };
+}
+
+/** Verify a submitted token. Returns true when allowed (incl. fail-open). */
+export async function verifyCaptcha(token: string | null, remoteIp?: string): Promise<boolean> {
+  const cfg = await captchaConfig();
+  if (cfg.provider === "none" || !cfg.siteKey) return true;
+
+  const secretKey = cfg.provider === "turnstile" ? "turnstile_secret" : "recaptcha_secret";
+  const secret = (await siteSettings.get(secretKey, "")) ?? "";
+  if (!secret) return true; // configured but no secret — don't hard-block
+  if (!token) return false;
+
+  const url = cfg.provider === "turnstile" ? TURNSTILE_URL : RECAPTCHA_URL;
+  const body = new URLSearchParams({ secret, response: token });
+  if (remoteIp) body.set("remoteip", remoteIp);
+
+  try {
+    const controller = new AbortController();
+    const timer = setTimeout(() => controller.abort(), 5000);
+    const res = await fetch(url, {
+      method: "POST",
+      headers: { "content-type": "application/x-www-form-urlencoded" },
+      body,
+      signal: controller.signal,
+      cache: "no-store",
+    });
+    clearTimeout(timer);
+    const data = (await res.json()) as { success?: boolean };
+    return data?.success === true;
+  } catch {
+    // Network/timeout — fail-open so a provider outage can't lock out signups.
+    return true;
+  }
+}