Add startup management functionality to the agent. Implement API endpoints for enabling and disabling startup, and update the web interface to reflect the current startup state.

lib/agent/web/index.html

@@ -62,6 +62,7 @@
       border-color: var(--accent);
       color: #fff;
     }
+    button:disabled { opacity: 0.45; cursor: default; }
     .panel {
       display: none;
       background: var(--card);
@@ -142,6 +143,11 @@
         <button id="refresh-status" class="primary" type="button">Refresh</button>
       </div>
       <dl id="status-fields"></dl>
+      <div class="row" style="margin-top:1rem">
+        <span id="startup-state" class="meta">Startup: —</span>
+        <button id="startup-add" type="button">Add to startup</button>
+        <button id="startup-remove" type="button">Remove from startup</button>
+      </div>
     </section>
     <section id="files" class="panel">
       <div class="row">