Update login authentication documentation with captcha and deployment context

- Added captcha requirement (simple math problem) to login steps
- Noted future plan to make captcha optional via system setting
- Clarified HTTPS context for browser security:
  - Only relevant for external access via domain name
  - Not applicable for internal IP-based deployments
- Marked Mozilla Firefox as recommended browser (most tested)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

containers/backupchecks/src/templates/documentation/users/login-authentication.html

@@ -23,10 +23,16 @@
   <li>You will be automatically redirected to the login page if not authenticated</li>
   <li>Enter your <strong>username</strong> in the username field</li>
   <li>Enter your <strong>password</strong> in the password field</li>
+  <li>Complete the <strong>captcha</strong> by solving the simple math problem (e.g., "3 + 5 = ?")</li>
   <li>Click the <strong>Login</strong> button</li>
 </ol>
 
-<p>If your credentials are correct, you will be redirected to the dashboard.</p>
+<p>If your credentials are correct and the captcha is solved, you will be redirected to the dashboard.</p>
+
+<div class="doc-callout doc-callout-info">
+  <strong>📝 Future Change:</strong><br>
+  The captcha requirement is planned to become optional via a system setting. Since BackupChecks is typically deployed in restricted local environments, the captcha may be disabled to streamline the login process.
+</div>
 
 <h3>First Login</h3>
 
@@ -147,12 +153,17 @@
 <h3>Browser Security</h3>
 
 <ul>
-  <li><strong>Use HTTPS:</strong> Ensure you're connecting via HTTPS (check for the padlock icon in your browser)</li>
+  <li><strong>Use HTTPS When Applicable:</strong> If BackupChecks is exposed externally via a domain name, ensure you're connecting via HTTPS (check for the padlock icon in your browser). For internal deployments accessed via IP address, HTTPS may not be configured.</li>
   <li><strong>Keep Browser Updated:</strong> Use the latest version of your browser for security patches</li>
-  <li><strong>Avoid Public WiFi:</strong> Don't log in from untrusted networks without a VPN</li>
+  <li><strong>Avoid Public WiFi:</strong> If accessing externally, don't log in from untrusted networks without a VPN</li>
   <li><strong>Clear Cookies on Shared Computers:</strong> Clear browser data after using a shared machine</li>
 </ul>
 
+<div class="doc-callout doc-callout-info">
+  <strong>💡 Deployment Context:</strong><br>
+  BackupChecks is typically deployed in restricted internal environments (accessed via IP address). For external access via a public domain, HTTPS should be configured using a reverse proxy or certificate.
+</div>
+
 <div class="doc-callout doc-callout-warning">
   <strong>⚠️ Security Alert:</strong><br>
   If you suspect unauthorized access to your account, contact your administrator immediately to reset your password and review audit logs.
@@ -199,36 +210,41 @@
     <tr>
       <th>Browser</th>
       <th>Minimum Version</th>
-      <th>Recommended</th>
+      <th>Status</th>
     </tr>
   </thead>
   <tbody>
     <tr>
-      <td>Google Chrome</td>
+      <td><strong>Mozilla Firefox</strong></td>
-      <td>90+</td>
+      <td>88+</td>
-      <td>Latest stable</td>
+      <td><strong>Recommended - Most tested</strong></td>
     </tr>
     <tr>
-      <td>Mozilla Firefox</td>
+      <td>Google Chrome</td>
-      <td>88+</td>
+      <td>90+</td>
-      <td>Latest stable</td>
+      <td>Supported</td>
     </tr>
     <tr>
       <td>Microsoft Edge</td>
       <td>90+</td>
-      <td>Latest stable</td>
+      <td>Supported</td>
     </tr>
     <tr>
       <td>Safari</td>
       <td>14+</td>
-      <td>Latest stable</td>
+      <td>Supported</td>
     </tr>
   </tbody>
 </table>
 
-<div class="doc-callout doc-callout-info">
+<div class="doc-callout doc-callout-tip">
-  <strong>💡 Note:</strong><br>
+  <strong>💡 Best Experience:</strong><br>
-  Internet Explorer is not supported. Please use a modern browser for the best experience.
+  Mozilla Firefox is the most thoroughly tested browser for BackupChecks and provides the best experience. While other modern browsers are supported, Firefox is recommended for optimal compatibility.
+</div>
+
+<div class="doc-callout doc-callout-warning">
+  <strong>⚠️ Not Supported:</strong><br>
+  Internet Explorer is not supported. Please use a modern browser (Firefox recommended).
 </div>
 
 <h2>Next Steps</h2>