Add player functionality with HLS support and API integration

- Implemented a new Player class in player.js to handle audio playback, including HLS support using hls.js.
- Created a shared API module in api.js for making HTTP requests with proper error handling.
- Added DOM utility functions in dom.js for creating and clearing elements.
- Introduced WebSocket connection handling in ws.js for real-time updates.
- Developed a comprehensive CSS stylesheet for styling the application, including a high-contrast theme.

server/sources/radiobrowser.js

@@ -0,0 +1,65 @@
+// Thin wrapper around the Radio-Browser community API.
+// Docs: https://api.radio-browser.info/
+
+const SERVERS = [
+  'https://de1.api.radio-browser.info',
+  'https://nl1.api.radio-browser.info',
+  'https://at1.api.radio-browser.info'
+];
+
+let activeServer = SERVERS[0];
+
+async function rb(path, params) {
+  const url = new URL(path, activeServer);
+  if (params) for (const [k, v] of Object.entries(params)) {
+    if (v != null) url.searchParams.set(k, String(v));
+  }
+  const res = await fetch(url, { headers: { 'User-Agent': 'OnlineRadioExplorer/0.1' } });
+  if (!res.ok) throw new Error(`Radio-Browser ${res.status}`);
+  return res.json();
+}
+
+export async function search({ name, country, tag, limit = 30 }) {
+  const list = await rb('/json/stations/search', {
+    name, country, tag, limit, hidebroken: true, order: 'votes', reverse: true
+  });
+  return list.map(toCanonical);
+}
+
+export async function byUuid(uuid) {
+  const list = await rb('/json/stations/byuuid', { uuids: uuid });
+  return list[0] ? toCanonical(list[0]) : null;
+}
+
+function detectFormat(codec, url) {
+  const c = (codec || '').toLowerCase();
+  if (c.includes('mp3')) return 'mp3';
+  if (c.includes('aac')) return 'aac';
+  if (c.includes('ogg') || c.includes('vorbis') || c.includes('opus')) return 'ogg';
+  if (url?.endsWith('.m3u8')) return 'hls';
+  if (url?.endsWith('.m3u'))  return 'm3u';
+  if (url?.endsWith('.pls'))  return 'pls';
+  return 'unknown';
+}
+
+function toCanonical(s) {
+  return {
+    uuid: s.stationuuid || undefined,
+    name: s.name,
+    slug: `rb-${s.stationuuid}`,
+    homepage: s.homepage || null,
+    country: s.countrycode || s.country || null,
+    genres: (s.tags || '').split(',').map((t) => t.trim()).filter(Boolean),
+    description: null,
+    image_url: s.favicon || null,
+    source: 'radiobrowser',
+    source_ref: s.stationuuid,
+    streams: [{
+      url: s.url_resolved || s.url,
+      format: detectFormat(s.codec, s.url_resolved || s.url),
+      bitrate: s.bitrate || null,
+      label: s.codec ? `${s.codec} ${s.bitrate || ''}`.trim() : null,
+      priority: 0
+    }]
+  };
+}