Verify mobile geometry and themed media icons across browsers

frontend/media-icons.test.js

@@ -0,0 +1,19 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const { readdirSync, readFileSync } = require('node:fs');
+const { join } = require('node:path');
+
+test('download and offline icons never use emoji or text glyphs', () => {
+  // Arrow keys are prose, not action icons. Exact lines prevent new exceptions.
+  const allow = new Map([
+    ['index.html', new Set(['<div class="shortcut-row"><kbd>↑</kbd><kbd>↓</kbd><span>Volume up / down</span></div>'])],
+    ['admin.html', new Set(['<span class="muted" style="font-size:12.5px">Shortcuts: <code>Space</code> stamp (Tap-sync) · <code>S</code> stamp selected · <code>K</code> play · <code>↑↓</code> select · <code>⌘/Ctrl S</code> save</span>'])],
+  ]);
+  const failures=[];
+  for (const file of readdirSync(__dirname).filter(f=>/\.(js|html|css)$/.test(f) && !f.endsWith('.test.js'))) {
+    readFileSync(join(__dirname,file),'utf8').split('\n').forEach((line,i)=>{
+      if (/[⬇⤓⇩💾📥↓]/u.test(line) && !allow.get(file)?.has(line.trim())) failures.push(`${file}:${i+1}`);
+    });
+  }
+  assert.deepEqual(failures,[]);
+});