WiFi screen: Ctrl+Alt+Super+W, gated by the unlock PIN/password

The WiFi screen now opens with Ctrl+Alt+Super+W, which is easier to
press than the five-key chord. The Shift+W+S+F+H chord and
Ctrl+Alt+Shift+Super+W are removed. Fn isn't part of the combo: most
keyboards never send it to the computer.

With password protection on, the screen asks for the unlock code: the
PIN pad for a PIN, a password field for a password. It shares the
lock screen's wrong-code slowdown. With protection off, it falls back
to the hidden-sites PIN as before. The lock screen's check now goes
through the same checkCode() helper.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Cjz8a58eB5P9sUweqd3NHm

kiosk-app/wifi.html

@@ -82,7 +82,7 @@
   <h2>📶 WiFi</h2>
 
   <div id="pin-step" class="hidden">
-    <label for="pin">Enter the PIN</label>
+    <label for="pin" id="pin-label">Enter the PIN</label>
     <input id="pin" type="password" inputmode="numeric" autocomplete="off">
     <div class="actions">
       <button class="primary" id="pin-ok">✓ OK</button>
@@ -242,6 +242,10 @@
 
     request('needs-pin').then(r => {
       if (r.ok && r.needsPin) {
+        if (r.codeType === 'password') {
+          $('pin-label').textContent = 'Enter the kiosk password';
+          $('pin').removeAttribute('inputmode');
+        }
         $('pin-step').classList.remove('hidden');
         $('pin').focus();
       } else {