feat: add recent plans history to homepage

components/plan-tracker.tsx

@@ -0,0 +1,35 @@
+"use client"
+
+import { useEffect } from "react"
+
+export function PlanTracker({ planId, title }: { planId: string, title: string }) {
+    useEffect(() => {
+        const stored = localStorage.getItem("csp_recent_plans")
+        let plans: { id: string, title: string, lastVisited: number }[] = []
+
+        if (stored) {
+            try {
+                plans = JSON.parse(stored)
+            } catch (e) {
+                console.error(e)
+            }
+        }
+
+        // Remove existing entry for this plan
+        plans = plans.filter(p => p.id !== planId)
+
+        // Add to top
+        plans.unshift({
+            id: planId,
+            title: title,
+            lastVisited: Date.now()
+        })
+
+        // Keep max 5
+        plans = plans.slice(0, 5)
+
+        localStorage.setItem("csp_recent_plans", JSON.stringify(plans))
+    }, [planId, title])
+
+    return null
+}