Add API documentation and underground station importer

- Introduced a new HTML documentation page for the oradio API, including a JavaScript file to handle dynamic content and API requests.
- Added a CSS file for styling the documentation page.
- Implemented an underground station importer script that fetches data from Radio-Browser and writes it to a JSON file.
- Created a stats module to compute and manage vote and play statistics for radio stations.
- Added a polyfill for modulepreload to ensure compatibility with older browsers.

server/ws.js

@@ -5,52 +5,52 @@ import { getUserBySession, readSessionToken } from './auth.js';
 const channels = new Map(); // userId -> Set<ws>
 
 export function attachWs(server) {
-  const wss = new WebSocketServer({ noServer: true });
+    const wss = new WebSocketServer({ noServer: true });
 
-  server.on('upgrade', (req, socket, head) => {
-    if (!req.url.startsWith('/ws')) return socket.destroy();
-    const token = readSessionToken(req);
-    const user = getUserBySession(token);
-    if (!user) {
-      socket.write('HTTP/1.1 401 Unauthorized\r\n\r\n');
-      socket.destroy();
-      return;
-    }
-    wss.handleUpgrade(req, socket, head, (ws) => {
-      ws.user = user;
-      addClient(user.id, ws);
-      ws.on('close', () => removeClient(user.id, ws));
-      ws.on('message', (raw) => {
-        let msg;
-        try { msg = JSON.parse(raw.toString()); } catch { return; }
-        // Re-broadcast every message to all connections of the same user.
-        // (e.g. phone sends `{type:"command", action:"play", stationId:7}` → kiosk receives)
-        broadcastToUser(user.id, msg, ws);
-      });
-      ws.send(JSON.stringify({ type: 'hello', user: { id: user.id, username: user.username, role: user.role } }));
+    server.on('upgrade', (req, socket, head) => {
+        if (!req.url.startsWith('/ws')) return socket.destroy();
+        const token = readSessionToken(req);
+        const user = getUserBySession(token);
+        if (!user) {
+            socket.write('HTTP/1.1 401 Unauthorized\r\n\r\n');
+            socket.destroy();
+            return;
+        }
+        wss.handleUpgrade(req, socket, head, (ws) => {
+            ws.user = user;
+            addClient(user.id, ws);
+            ws.on('close', () => removeClient(user.id, ws));
+            ws.on('message', (raw) => {
+                let msg;
+                try { msg = JSON.parse(raw.toString()); } catch { return; }
+                // Re-broadcast every message to all connections of the same user.
+                // (e.g. phone sends `{type:"command", action:"play", stationId:7}` → kiosk receives)
+                broadcastToUser(user.id, msg, ws);
+            });
+            ws.send(JSON.stringify({ type: 'hello', user: { id: user.id, username: user.username, role: user.role } }));
+        });
     });
-  });
 
-  return wss;
+    return wss;
 }
 
 function addClient(userId, ws) {
-  if (!channels.has(userId)) channels.set(userId, new Set());
-  channels.get(userId).add(ws);
+    if (!channels.has(userId)) channels.set(userId, new Set());
+    channels.get(userId).add(ws);
 }
 function removeClient(userId, ws) {
-  const set = channels.get(userId);
-  if (!set) return;
-  set.delete(ws);
-  if (!set.size) channels.delete(userId);
+    const set = channels.get(userId);
+    if (!set) return;
+    set.delete(ws);
+    if (!set.size) channels.delete(userId);
 }
 
 export function broadcastToUser(userId, msg, except) {
-  const set = channels.get(userId);
-  if (!set) return;
-  const payload = JSON.stringify(msg);
-  for (const ws of set) {
-    if (ws === except) continue;
-    if (ws.readyState === ws.OPEN) ws.send(payload);
-  }
+    const set = channels.get(userId);
+    if (!set) return;
+    const payload = JSON.stringify(msg);
+    for (const ws of set) {
+        if (ws === except) continue;
+        if (ws.readyState === ws.OPEN) ws.send(payload);
+    }
 }