feat: add metrics export as CSV/JSON (MON-04)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

neode-ui/src/views/Monitoring.vue

@@ -1,8 +1,20 @@
 <template>
   <div>
     <div class="hidden md:block mb-8">
-      <h1 class="text-3xl font-bold text-white mb-2">Monitoring</h1>
-      <p class="text-white/70">Real-time system metrics and container resource usage</p>
+      <div class="flex items-center justify-between">
+        <div>
+          <h1 class="text-3xl font-bold text-white mb-2">Monitoring</h1>
+          <p class="text-white/70">Real-time system metrics and container resource usage</p>
+        </div>
+        <div class="flex gap-2">
+          <button class="glass-button text-sm px-4 py-2" @click="exportMetrics('csv')">
+            Export CSV
+          </button>
+          <button class="glass-button text-sm px-4 py-2" @click="exportMetrics('json')">
+            Export JSON
+          </button>
+        </div>
+      </div>
     </div>
 
     <!-- Summary Cards -->
@@ -401,6 +413,32 @@ function formatAlertTime(timestamp: number): string {
   return d.toLocaleString()
 }
 
+async function exportMetrics(format: 'csv' | 'json') {
+  try {
+    const data = await rpcClient.call<{ csv?: string; data?: unknown[]; count: number }>({
+      method: 'monitoring.export',
+      params: { format, resolution: 'minute', count: 1440 },
+    })
+    let blob: Blob
+    let filename: string
+    if (format === 'csv' && data?.csv) {
+      blob = new Blob([data.csv], { type: 'text/csv' })
+      filename = `archipelago-metrics-${new Date().toISOString().slice(0, 10)}.csv`
+    } else {
+      blob = new Blob([JSON.stringify(data?.data ?? [], null, 2)], { type: 'application/json' })
+      filename = `archipelago-metrics-${new Date().toISOString().slice(0, 10)}.json`
+    }
+    const url = URL.createObjectURL(blob)
+    const a = document.createElement('a')
+    a.href = url
+    a.download = filename
+    a.click()
+    URL.revokeObjectURL(url)
+  } catch {
+    if (import.meta.env.DEV) console.warn('Failed to export metrics')
+  }
+}
+
 async function fetchCurrent() {
   try {
     const data = await rpcClient.call<MetricSnapshot | { status: string }>({