Add kiosk launcher downloads and player URL resolution

src/web/routes/common.js

@@ -1,7 +1,5 @@
 // Shared route helpers for web view rendering and player URL formatting.
 
-const PLAYER_PUBLIC_BASE_URL = (process.env.PLAYER_PUBLIC_BASE_URL || process.env.PLAYER_BASE_URL || 'http://localhost:3001').replace(/\/$/, '');
-
 function escapeHtml(value) {
   return String(value ?? '')
     .replace(/&/g, '&')
@@ -11,8 +9,13 @@ function escapeHtml(value) {
     .replace(/'/g, ''');
 }
 
-function screenPlayerUrl(slug) {
-  return `${PLAYER_PUBLIC_BASE_URL}/screen/${encodeURIComponent(slug)}`;
+function screenPlayerUrl(slug, baseUrl) {
+  const normalizedBaseUrl = String(baseUrl || '').trim().replace(/\/$/, '');
+  if (!normalizedBaseUrl) {
+    return '';
+  }
+
+  return `${normalizedBaseUrl}/screen/${encodeURIComponent(slug)}`;
 }
 
 module.exports = {