feat: display linked host agent badge on PVE nodes

- NodeGroupHeader shows '+ Host Agent' badge when node has linked agent
- NodeSummaryTable shows '+Agent' badge in the node row
- Filter out linked hosts from Managed Agents list (prevents duplication)

This provides visual feedback when a PVE node has enhanced monitoring
via an installed host agent.

frontend-modern/src/components/shared/NodeGroupHeader.tsx

@@ -44,13 +44,22 @@ export const NodeGroupHeader: Component<NodeGroupHeaderProps> = (props) => {
       <Show when={props.node.isClusterMember !== undefined}>
         <span
           class={`rounded px-2 py-0.5 text-[10px] font-medium whitespace-nowrap ${props.node.isClusterMember
-              ? 'bg-blue-100 text-blue-700 dark:bg-blue-900/40 dark:text-blue-300'
+            ? 'bg-blue-100 text-blue-700 dark:bg-blue-900/40 dark:text-blue-300'
-              : 'bg-slate-200 text-slate-600 dark:bg-slate-700/60 dark:text-slate-300'
+            : 'bg-slate-200 text-slate-600 dark:bg-slate-700/60 dark:text-slate-300'
             }`}
         >
           {props.node.isClusterMember ? props.node.clusterName : 'Standalone'}
         </span>
       </Show>
+
+      <Show when={props.node.linkedHostAgentId}>
+        <span
+          class="rounded px-2 py-0.5 text-[10px] font-medium whitespace-nowrap bg-purple-100 text-purple-700 dark:bg-purple-900/40 dark:text-purple-300"
+          title="Pulse host agent is installed on this node for enhanced metrics (temperatures, detailed disks, RAID status)"
+        >
+          + Host Agent
+        </span>
+      </Show>
     </div>
   );
 

frontend-modern/src/components/shared/NodeSummaryTable.tsx

@@ -533,6 +533,14 @@ export const NodeSummaryTable: Component<NodeSummaryTableProps> = (props) => {
                               {node!.isClusterMember ? node!.clusterName : 'Standalone'}
                             </span>
                           </Show>
+                          <Show when={isPVEItem && node!.linkedHostAgentId}>
+                            <span
+                              class="text-[9px] px-1 py-0 rounded font-medium whitespace-nowrap bg-purple-100 text-purple-700 dark:bg-purple-900/30 dark:text-purple-400"
+                              title="Pulse host agent installed for enhanced metrics"
+                            >
+                              +Agent
+                            </span>
+                          </Show>
                           <Show when={isPBSItem}>
                             <span class="text-[9px] px-1 py-0 rounded font-medium bg-purple-100 text-purple-700 dark:bg-purple-900/30 dark:text-purple-400">
                               PBS