feat(ui): integrate official NexusPBX logo and favicon (replace placeholder icon)

public/index.php

@@ -27,6 +27,8 @@ $appVersion = $appVerData['version'] ?? '1.5.0';
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <meta name="nexus-app-version" content="<?= htmlspecialchars($appVersion) ?>">
     <title>NexusPBX — Supervision & Gestion PJSIP sur Debian</title>
+    <link rel="icon" type="image/png" href="/assets/favicon.png?v=<?= file_exists(__DIR__ . '/assets/favicon.png') ? filemtime(__DIR__ . '/assets/favicon.png') : 1 ?>">
+    <link rel="apple-touch-icon" href="/assets/logo.png?v=<?= file_exists(__DIR__ . '/assets/logo.png') ? filemtime(__DIR__ . '/assets/logo.png') : 1 ?>">
     <script src="https://cdn.tailwindcss.com"></script>
     <script>
         tailwind.config = {
@@ -158,10 +160,8 @@ $appVersion = $appVerData['version'] ?? '1.5.0';
         <!-- Carte de connexion flottante avec effet Glassmorphism transparent et aéré -->
         <div class="relative z-10 w-full max-w-md bg-anthracite-900/60 backdrop-blur-2xl border border-white/15 rounded-3xl shadow-2xl shadow-black/50 p-8 sm:p-9 transition-all">
             <div class="flex items-center gap-3.5 mb-6">
-                <div class="w-12 h-12 rounded-xl bg-indigo-500/20 border border-indigo-400/40 flex items-center justify-center text-indigo-300 shadow-inner">
-                    <svg class="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                        <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M3 5a2 2 0 012-2h3.28a1 1 0 01.948.684l1.498 4.493a1 1 0 01-.502 1.21l-2.257 1.13a11.042 11.042 0 005.516 5.516l1.13-2.257a1 1 0 011.21-.502l4.493 1.498a1 1 0 01.684.949V19a2 2 0 01-2 2h-1C9.716 21 3 14.284 3 6V5z"/>
-                    </svg>
+                <div class="w-12 h-12 rounded-2xl bg-gradient-to-br from-cyan-500/15 via-indigo-500/20 to-purple-600/20 border border-cyan-400/30 flex items-center justify-center p-2 shadow-lg shadow-cyan-500/10 shrink-0">
+                    <img src="/assets/logo.png?v=<?= file_exists(__DIR__ . '/assets/logo.png') ? filemtime(__DIR__ . '/assets/logo.png') : 1 ?>" alt="NexusPBX Logo" class="w-full h-full object-contain filter drop-shadow">
                 </div>
                 <div>
                     <h1 class="text-xl font-bold text-white tracking-tight">NexusPBX</h1>
@@ -207,10 +207,8 @@ $appVersion = $appVerData['version'] ?? '1.5.0';
                 <div class="px-4 py-3.5 border-b border-anthracite-700/80 space-y-2.5">
                     <div class="flex items-center justify-between">
                         <div class="flex items-center gap-3">
-                            <div class="w-10 h-10 rounded-xl bg-gradient-to-br from-indigo-500/30 to-purple-600/20 border border-indigo-400/40 flex items-center justify-center text-indigo-300 shadow-lg shadow-indigo-500/10 shrink-0">
-                                <svg class="w-5 h-5 text-indigo-300" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                                    <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M3 5a2 2 0 012-2h3.28a1 1 0 01.948.684l1.498 4.493a1 1 0 01-.502 1.21l-2.257 1.13a11.042 11.042 0 005.516 5.516l1.13-2.257a1 1 0 011.21-.502l4.493 1.498a1 1 0 01.684.949V19a2 2 0 01-2 2h-1C9.716 21 3 14.284 3 6V5z"/>
-                                </svg>
+                            <div class="w-10 h-10 rounded-xl bg-gradient-to-br from-cyan-500/15 via-indigo-500/20 to-purple-600/20 border border-cyan-400/30 flex items-center justify-center p-1.5 shadow-lg shadow-cyan-500/10 shrink-0">
+                                <img src="/assets/logo.png?v=<?= file_exists(__DIR__ . '/assets/logo.png') ? filemtime(__DIR__ . '/assets/logo.png') : 1 ?>" alt="NexusPBX Logo" class="w-full h-full object-contain filter drop-shadow">
                             </div>
                             <div>
                                 <div class="flex items-center gap-2">