espid2sensor: Passwort-Reset-Modal statt Browser-prompt(), Absturz bei Nicht-Admin-Login behoben

- Ersetzt window.prompt() für den Passwort-Reset in der User-Liste durch
  ein eigenes, zum bestehenden Bestätigungs-Modal passendes Popup
  (showInputModal), analog zum vorhandenen showModal für Löschbestätigungen.
- Behebt ReferenceError beim Login als Nicht-Admin: userCancelBtn wurde als
  impliziter globaler Bezeichner referenziert statt über
  document.getElementById, existiert aber nur im admin-only User-Tab-HTML.
  Für Nicht-Admins riss das den kompletten Setup-Block (Tabs, Liste laden) ab.

espid2sensor/public/global.js

@@ -112,6 +112,8 @@ document.addEventListener('DOMContentLoaded', () => {
   const tableBody = document.querySelector('#entriesTable tbody');
   const tabInput = document.getElementById('tabInput');
   const tabList = document.getElementById('tabList');
+  const cancelBtn = document.getElementById('cancelBtn');
+  const userCancelBtn = document.getElementById('userCancelBtn');
 
 
   // Modal für Fehleranzeige
@@ -175,6 +177,73 @@ function showModal(message, showCancelButton, callback) {
     }
   };
 }
+
+  // Modal für Passwort-Eingabe (z.B. Passwort-Reset aus der User-Liste)
+  function showInputModal(message, callback) {
+    document.querySelectorAll('.custom-modal-popup').forEach(m => m.remove());
+
+    let modal = document.createElement('div');
+    modal.className = 'custom-modal-popup';
+
+    let box = document.createElement('div');
+    box.className = 'custom-modal-box';
+
+    let msg = document.createElement('div');
+    msg.className = 'custom-modal-msg';
+    msg.textContent = message;
+    box.appendChild(msg);
+
+    let input = document.createElement('input');
+    input.type = 'password';
+    input.className = 'custom-modal-input';
+    box.appendChild(input);
+
+    let btndiv = document.createElement('div');
+    btndiv.className = 'twobuttons';
+
+    const close = () => {
+      if (modal.parentNode) modal.parentNode.removeChild(modal);
+    };
+
+    let btnCancel = document.createElement('button');
+    btnCancel.className = 'custom-modal-btn';
+    btnCancel.textContent = 'Abbruch';
+    btnCancel.onclick = () => {
+      close();
+      callback(null);
+    };
+    btndiv.appendChild(btnCancel);
+
+    let btnOk = document.createElement('button');
+    btnOk.className = 'custom-modal-btn';
+    btnOk.textContent = 'OK';
+    btnOk.onclick = () => {
+      const value = input.value;
+      close();
+      callback(value || null);
+    };
+    btndiv.appendChild(btnOk);
+
+    box.appendChild(btndiv);
+    modal.appendChild(box);
+    document.body.appendChild(modal);
+    input.focus();
+
+    input.addEventListener('keydown', (e) => {
+      if (e.key === 'Enter') {
+        e.preventDefault();
+        btnOk.click();
+      }
+    });
+
+    modal.onclick = (e) => {
+      if (e.target === modal) {
+        close();
+        callback(null);
+      }
+    };
+  }
+
   // Sensornummer nur Zahlen erlauben
   sensorNumberInput.addEventListener('input', () => {
     sensorNumberInput.value = sensorNumberInput.value.replace(/\D/g, '');
@@ -464,9 +533,9 @@ function showModal(message, showCancelButton, callback) {
       });
 
       document.querySelectorAll('.resetUserBtn').forEach(btn => {
-        btn.addEventListener('click', async () => {
+        btn.addEventListener('click', () => {
           const email = btn.getAttribute('data-email');
-          const newPassword = prompt(`Neues Passwort für ${email}:`);
+          showInputModal(`Neues Passwort für ${email}:`, async (newPassword) => {
             if (!newPassword) return;
             try {
               const res = await fetch('/api/resetPassword', {
@@ -481,6 +550,7 @@ function showModal(message, showCancelButton, callback) {
             }
           });
         });
+      });
 
       document.querySelectorAll('.deleteUserBtn').forEach(btn => {
         btn.addEventListener('click', () => {
@@ -510,7 +580,7 @@ function showModal(message, showCancelButton, callback) {
   saveBtn.addEventListener('click', saveEntry);
   refreshBtn.addEventListener('click', loadEntries);
   cancelBtn.addEventListener('click', () => clearForm(true));
-  userCancelBtn.addEventListener('click', () => clearUserForm(true));
+  if (userCancelBtn) userCancelBtn.addEventListener('click', () => clearUserForm(true));
 
   tabInput.addEventListener('click', () => showTab('input'))
   tabList.addEventListener('click', () => showTab('list'))

espid2sensor/public/styles.css

@@ -56,6 +56,12 @@
   color: red;
 }
 
+.custom-modal-input {
+  display: block;
+  width: 80%;
+  margin: 0 auto 1.5rem auto;
+}
+
 .custom-modal-btn {
   padding: 0.8rem 2.5rem;
   font-size: 1.1rem;