fix(ui): remove GitHub and LinkedIn buttons from top header bar; keep header clean

frontend/index.html

@@ -99,8 +99,6 @@
         <div class="logo-container">
             <span class="logo-text">AETERNA<span class="highlight">AI</span></span>
             <span class="version-tag">v4.0.0 (Eco-Twin)</span>
-            <a href="https://github.com/FARILtau72/Aeterna-Ai" target="_blank" rel="noopener noreferrer" style="color:#00f2fe; text-decoration:none; font-family:'JetBrains Mono',monospace; font-size:11px; margin-left:10px; font-weight:600; background:rgba(0,242,254,0.1); padding:3px 8px; border-radius:4px; border:1px solid rgba(0,242,254,0.3);">GitHub</a>
-            <a href="https://www.linkedin.com/in/faril-putra-pratama-81561a280/" target="_blank" rel="noopener noreferrer" style="color:#00f2fe; text-decoration:none; font-family:'JetBrains Mono',monospace; font-size:11px; margin-left:6px; font-weight:600; background:rgba(0,242,254,0.1); padding:3px 8px; border-radius:4px; border:1px solid rgba(0,242,254,0.3);">LinkedIn</a>
         </div>
         <nav class="nav-links">
             <button class="nav-btn active" data-target="page-home">HOME</button>