Add Week 3 polish and late-game features

VC funding system (seed through IPO with requirements gating), 15
achievements with engine checker, model tuning presets and unlockable
sliders, overload policy controls, open-source mechanic with reputation
boost, enhanced Recharts analytics (subscriber/reputation/revenue vs
expenses charts), M&A acquisition system, sidebar NEW badges on era
transitions, tutorial hints, and wired-up settings toggles.

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

apps/web/src/components/layout/Sidebar.tsx

@@ -1,6 +1,7 @@
+import { useState, useEffect, useRef } from 'react';
 import {
   LayoutDashboard, Server, FlaskConical, Brain,
-  TrendingUp, Users, Database, Swords, DollarSign, Settings,
+  TrendingUp, Users, Database, Swords, DollarSign, Settings, Trophy,
 } from 'lucide-react';
 import { useGameStore, type ActivePage } from '@/store';
 
@@ -14,6 +15,7 @@ const NAV_ITEMS: { page: ActivePage; label: string; icon: typeof LayoutDashboard
   { page: 'talent', label: 'Talent', icon: Users, era: 'scaleup' },
   { page: 'data', label: 'Data', icon: Database, era: 'scaleup' },
   { page: 'competitors', label: 'Competitors', icon: Swords, era: 'scaleup' },
+  { page: 'achievements', label: 'Achievements', icon: Trophy },
   { page: 'settings', label: 'Settings', icon: Settings },
 ];
 
@@ -26,6 +28,32 @@ export function Sidebar() {
   const eraOrder = ['startup', 'scaleup', 'bigtech', 'agi'];
   const currentEraIdx = eraOrder.indexOf(era);
 
+  const seenEraRef = useRef(era);
+  const [newPages, setNewPages] = useState<Set<string>>(new Set());
+
+  useEffect(() => {
+    if (era !== seenEraRef.current) {
+      const oldIdx = eraOrder.indexOf(seenEraRef.current);
+      const newIdx = eraOrder.indexOf(era);
+      if (newIdx > oldIdx) {
+        const newlyVisible = NAV_ITEMS
+          .filter(item => item.era && eraOrder.indexOf(item.era) > oldIdx && eraOrder.indexOf(item.era) <= newIdx)
+          .map(item => item.page);
+        setNewPages(prev => new Set([...prev, ...newlyVisible]));
+      }
+      seenEraRef.current = era;
+    }
+  }, [era]);
+
+  const handleNavClick = (page: ActivePage) => {
+    setActivePage(page);
+    setNewPages(prev => {
+      const next = new Set(prev);
+      next.delete(page);
+      return next;
+    });
+  };
+
   return (
     <aside className="w-56 bg-surface-900 border-r border-surface-700 flex flex-col h-screen">
       <div className="p-4 border-b border-surface-700">
@@ -40,10 +68,11 @@ export function Sidebar() {
           if (requiredEra && eraOrder.indexOf(requiredEra) > currentEraIdx) return null;
 
           const isActive = activePage === page;
+          const isNew = newPages.has(page);
           return (
             <button
               key={page}
-              onClick={() => setActivePage(page)}
+              onClick={() => handleNavClick(page)}
               className={`w-full flex items-center gap-3 px-4 py-2.5 text-sm transition-colors ${
                 isActive
                   ? 'bg-accent/10 text-accent-light border-r-2 border-accent'
@@ -52,6 +81,9 @@ export function Sidebar() {
             >
               <Icon size={18} />
               {label}
+              {isNew && (
+                <span className="ml-auto text-[10px] font-bold bg-accent text-white px-1.5 py-0.5 rounded">NEW</span>
+              )}
             </button>
           );
         })}