Add join captcha gate

server.js

@@ -5,6 +5,7 @@ import { randomUUID } from "node:crypto";
 
 const port = Number(process.env.PORT || 3000);
 const host = process.env.HOST || "127.0.0.1";
+const captchaPassphrase = process.env.KKKMEET_CAPTCHA_PASSPHRASE || "kkkmeet";
 const publicDir = join(process.cwd(), "public");
 const rooms = new Map();
 const watchStates = new Map();
@@ -48,6 +49,10 @@ function normalizeClientId(value) {
   return /^[a-z0-9_-]{16,80}$/i.test(normalized) ? normalized : "";
 }
 
+function captchaAccepted(value) {
+  return String(value || "") === captchaPassphrase;
+}
+
 function normalizePlaylist(playlist) {
   if (!Array.isArray(playlist)) return [];
 
@@ -137,6 +142,11 @@ const server = http.createServer(async (req, res) => {
 
   try {
     if (req.method === "GET" && url.pathname.startsWith("/events/")) {
+      if (!captchaAccepted(url.searchParams.get("captcha"))) {
+        sendJson(res, 403, { error: "Captcha passphrase is required." });
+        return;
+      }
+
       const roomId = url.pathname.split("/").at(-1) || defaultRoomId;
       const displayName = normalizeName(url.searchParams.get("name"));
       const clientId = normalizeClientId(url.searchParams.get("clientId"));
@@ -180,6 +190,16 @@ const server = http.createServer(async (req, res) => {
       return;
     }
 
+    if (req.method === "GET" && url.pathname === "/config") {
+      sendJson(res, 200, {
+        captcha: {
+          enabled: true,
+          passphrase: captchaPassphrase
+        }
+      });
+      return;
+    }
+
     if (req.method === "POST" && url.pathname.startsWith("/room-event/")) {
       const roomId = url.pathname.split("/").at(-1) || defaultRoomId;
       const payload = await parseJson(req);