Fix max update depth crash on Infrastructure page

ToastContainer's useEffect had `seen` (a Set state) in its dependency
array — each setSeen created a new Set, re-fired the effect, and under
rapid notifications cascaded past React's 50-update limit. Replaced
with a ref since seen doesn't need to trigger re-renders.

Also added useShallow to DataCenterCard's pipeline selector to prevent
.filter() from causing spurious re-renders on unrelated store changes.

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

apps/web/src/components/common/ToastContainer.tsx

@@ -1,4 +1,4 @@
-import { useEffect, useState } from 'react';
+import { useEffect, useState, useRef } from 'react';
 import { X, CheckCircle, AlertTriangle, Info, AlertCircle } from 'lucide-react';
 import { useGameStore, type GameNotification } from '@/store';
 
@@ -10,23 +10,19 @@ export function ToastContainer() {
   const notifications = useGameStore((s) => s.notifications);
   const dismissNotification = useGameStore((s) => s.dismissNotification);
   const [toasts, setToasts] = useState<Toast[]>([]);
-  const [seen, setSeen] = useState(new Set<string>());
+  const seenRef = useRef(new Set<string>());
 
   useEffect(() => {
-    const newNotifs = notifications.filter(n => !n.read && !seen.has(n.id));
+    const newNotifs = notifications.filter(n => !n.read && !seenRef.current.has(n.id));
     if (newNotifs.length === 0) return;
 
-    setSeen(prev => {
-      const next = new Set(prev);
-      for (const n of newNotifs) next.add(n.id);
-      return next;
-    });
+    for (const n of newNotifs) seenRef.current.add(n.id);
 
     setToasts(prev => [
       ...newNotifs.map(n => ({ ...n, exiting: false })),
       ...prev,
     ].slice(0, 5));
-  }, [notifications, seen]);
+  }, [notifications]);
 
   useEffect(() => {
     if (toasts.length === 0) return;

apps/web/src/pages/InfrastructurePage.tsx

@@ -1,6 +1,7 @@
-import { useState } from 'react';
+import { useState, useMemo } from 'react';
 import { Plus, Server, MapPin, Zap, HardDrive, Wrench, ChevronDown, ChevronUp, Thermometer, Shield, X } from 'lucide-react';
 import { useGameStore } from '@/store';
+import { useShallow } from 'zustand/shallow';
 import {
   formatMoney, formatNumber, formatPercent,
   LOCATION_CONFIGS, DC_TIER_CONFIGS, RACK_SKU_CONFIGS,
@@ -105,7 +106,7 @@ function CapacityBar({ label, used, max, unit, icon: Icon }: {
 
 function DataCenterCard({ dcId }: { dcId: string }) {
   const dc = useGameStore((s) => s.infrastructure.dataCenters.find(d => d.id === dcId))!;
-  const pipelineForDc = useGameStore((s) => s.infrastructure.rackPipeline.filter(o => o.dataCenterId === dcId));
+  const pipelineForDc = useGameStore(useShallow((s) => s.infrastructure.rackPipeline.filter(o => o.dataCenterId === dcId)));
   const money = useGameStore((s) => s.economy.money);
   const era = useGameStore((s) => s.meta.currentEra);
   const completedResearch = useGameStore((s) => s.research.completedResearch);