Initial commit: Eventify Server Health Monitor

Full-stack real-time server monitoring dashboard with:
- Express.js backend with SSH-based metrics collection
- React + TypeScript + Tailwind CSS + shadcn/ui frontend
- CPU, memory, disk, Docker container, and Nginx monitoring
- Pure SVG charts (CPU area chart + memory donut)
- Gilroy font, 10s auto-refresh polling
- Multi-page dashboard with sidebar navigation

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

client/src/components/dashboard/RefreshControl.tsx

@@ -0,0 +1,45 @@
+import { useMemo } from "react"
+import { cn } from "@/lib/utils"
+
+interface RefreshControlProps {
+  lastUpdated: string | null
+  isConnected: boolean
+}
+
+function formatRelativeTime(timestamp: string): string {
+  const diff = Date.now() - new Date(timestamp).getTime()
+  const seconds = Math.floor(diff / 1000)
+  if (seconds < 5) return "just now"
+  if (seconds < 60) return `${seconds}s ago`
+  const minutes = Math.floor(seconds / 60)
+  return `${minutes}m ago`
+}
+
+export function RefreshControl({ lastUpdated, isConnected }: RefreshControlProps) {
+  const relativeTime = useMemo(() => {
+    if (!lastUpdated) return "..."
+    return formatRelativeTime(lastUpdated)
+  }, [lastUpdated])
+
+  return (
+    <div className="flex items-center gap-2 rounded-lg border px-3 py-1.5">
+      <span
+        className={cn(
+          "relative flex size-2",
+          isConnected ? "text-green-500" : "text-muted-foreground"
+        )}
+      >
+        {isConnected && (
+          <span className="absolute inline-flex size-full animate-ping rounded-full bg-green-400 opacity-75" />
+        )}
+        <span
+          className={cn(
+            "relative inline-flex size-2 rounded-full",
+            isConnected ? "bg-green-500" : "bg-muted-foreground"
+          )}
+        />
+      </span>
+      <span className="text-xs text-muted-foreground">{relativeTime}</span>
+    </div>
+  )
+}