Feat: White-label web UI branding for subpath deployments

When the web remote desktop is mounted under another domain's subpath
(YAMA_WEB_BASE_PATH non-empty), read the product title from
YAMA_WEB_BRAND_NAME, substitute it for the SimpleRemoter titles and
PWA manifest name, and strip the security notice and website links.
The brand name is JSON- and HTML-escaped so operator input can't
produce malformed output. Served from the domain root, the official
SimpleRemoter branding is left unchanged.

Co-Authored-By: deepseek-v4-pro

server/web/index.html

@@ -3,11 +3,11 @@
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no, viewport-fit=cover">
-    <title>SimpleRemoter</title>
+    <title>__BRAND_NAME__</title>
     <!-- PWA / iOS Standalone App Support -->
     <meta name="apple-mobile-web-app-capable" content="yes">
     <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent">
-    <meta name="apple-mobile-web-app-title" content="Remoter">
+    <meta name="apple-mobile-web-app-title" content="__BRAND_NAME__">
     <meta name="mobile-web-app-capable" content="yes">
     <meta name="theme-color" content="#1a1a2e">
     <link rel="manifest" href="__BASE_PATH__/manifest.json">
@@ -1154,7 +1154,7 @@
 
     <div id="login-page" class="page active">
         <div class="login-form">
-            <h1>SimpleRemoter</h1>
+            <h1>__BRAND_NAME__</h1>
             <div id="ws-status" class="conn-status disconnected">Connecting...</div>
             <input type="text" id="username" placeholder="Username" value="admin">
             <div class="password-wrapper">
@@ -1164,14 +1164,18 @@
             <button id="login-btn" onclick="login()" disabled>Login</button>
             <div id="login-error" class="error-msg"></div>
             <div class="login-footer">
+                <!--BRAND-NOTICE-START-->
                 <div class="security-notice">
                     <strong>&#x26A0; Security Notice</strong>
                     This software is for lawful, authorized, and legitimate use only. You are solely responsible for your use and for complying with applicable law. The developer assumes no liability.
                 </div>
+                <!--BRAND-NOTICE-END-->
+                <!--BRAND-LINKS-START-->
                 <div class="login-links">
                     <a href="https://simpleremoter.com/" target="_blank">&#x1F310; Website</a>
                     <a href="https://git.simpleremoter.com/" target="_blank">&#x1F4E6; Source Code</a>
                 </div>
+                <!--BRAND-LINKS-END-->
             </div>
         </div>
     </div>