fix: resolve runtime issues with game loop, tabs, and error handling

- Fix game loop store mismatch (page.tsx now uses modular stores matching gameHooks.ts)
- Fix StatsTab.tsx type errors (signedPacts now from usePrestigeStore)
- Fix React hooks violations (all hooks called before conditional returns)
- Add ErrorBoundary to page.tsx for better error handling
- Fix getStudySpeedMultiplier called with correct arguments
- Build succeeds consistently

src/components/game/tabs/StatsTab.tsx

@@ -5,7 +5,6 @@ import { getTierMultiplier } from '@/lib/game/skill-evolution';
 import { hasSpecial, SPECIAL_EFFECTS } from '@/lib/game/effects';
 import { getUnifiedEffects } from '@/lib/game/effects';
 import { fmt, fmtDec, computeMaxMana, computeRegen, computeClickMana, getMeditationBonus, getIncursionStrength, getStudySpeedMultiplier, getStudyCostMultiplier } from '@/lib/game/stores';
-import type { UnifiedEffects } from '@/lib/game/types';
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
 import { Badge } from '@/components/ui/badge';
 import { Separator } from '@/components/ui/separator';
@@ -30,13 +29,13 @@ export function StatsTab() {
   const insight = usePrestigeStore((s) => s.insight);
   const totalInsight = usePrestigeStore((s) => s.totalInsight);
   const memorySlots = usePrestigeStore((s) => s.memorySlots);
+  const signedPacts = usePrestigeStore((s) => s.signedPacts);
   
   const elements = useManaStore((s) => s.elements);
   const totalManaGathered = useManaStore((s) => s.totalManaGathered);
   const rawMana = useManaStore((s) => s.rawMana);
   const meditateTicks = useManaStore((s) => s.meditateTicks);
   
-  const signedPacts = useCombatStore((s) => s.signedPacts);
   const maxFloorReached = useCombatStore((s) => s.maxFloorReached);
   const spells = useCombatStore((s) => s.spells);
 
@@ -46,8 +45,8 @@ export function StatsTab() {
     skillTiers, 
     equippedInstances: {}, 
     equipmentInstances: {} 
-  }) as UnifiedEffects;
-  
+  });
+
   // Compute derived stats
   const maxMana = computeMaxMana({ 
     skills, 
@@ -70,17 +69,15 @@ export function StatsTab() {
     skillTiers 
   });
   
-  // Get meditation multiplier
   const meditationMultiplier = getMeditationBonus(meditateTicks, skills, upgradeEffects.meditationEfficiency);
   
-  // Get incursion strength
   const day = useGameStore((s) => s.day);
   const hour = useGameStore((s) => s.hour);
   const incursionStrength = getIncursionStrength(day, hour);
-  
+
   // Effective regen with incursion penalty
   const effectiveRegenWithSpecials = baseRegen * (1 - incursionStrength);
-  
+
   // Mana Cascade bonus
   const manaCascadeBonus = hasSpecial(upgradeEffects, SPECIAL_EFFECTS.MANA_CASCADE)
     ? Math.floor(maxMana / 100) * 0.1
@@ -93,11 +90,11 @@ export function StatsTab() {
 
   // Effective regen
   const effectiveRegen = (effectiveRegenWithSpecials + manaCascadeBonus + manaWaterfallBonus) * meditationMultiplier;
-  
+
   // Get study speed/cost multipliers
   const studySpeedMult = getStudySpeedMultiplier(skills);
   const studyCostMult = getStudyCostMultiplier(skills);
-  
+
   // Check special effects
   const hasManaWaterfall = hasSpecial(upgradeEffects, SPECIAL_EFFECTS.MANA_WATERFALL);
   const hasFlowSurge = hasSpecial(upgradeEffects, SPECIAL_EFFECTS.FLOW_SURGE);