fix: Object.values null safety + Docker dev build

- Change Dockerfile to use development build (better error messages)
- Add || {} fallbacks to all Object.values() calls accessing state
- Fixes "Cannot convert undefined or null to object" browser error during SSR/hydration
- Verified TypeScript compilation and Next.js build successful

Files modified:
- Dockerfile
- src/app/page.tsx
- src/components/game/tabs/StatsTab.tsx
- src/components/game/StatsTab/LoopStatsSection.tsx
- src/components/game/StatsTab/ElementStatsSection.tsx
- src/components/game/tabs/AttunementsTab.tsx
- src/components/game/tabs/GolemancyTab.tsx
- src/lib/game/effects.ts
- src/lib/game/utils/combat-utils.ts
- src/lib/game/crafting-loot.ts
- src/components/game/LootInventory/LootInventoryDisplay.tsx
- src/components/game/LootInventory/index.tsx
- src/components/game/crafting/EnchantmentDesigner/utils.ts

src/components/game/LootInventory/index.tsx

@@ -55,7 +55,7 @@ export function LootInventoryDisplay({
   const [deleteConfirm, setDeleteConfirm] = useState<{ type: 'material' | 'equipment'; id: string; name: string } | null>(null);
 
   // Count items
-  const materialCount = Object.values(inventory.materials).reduce((a: number, b: number) => a + b, 0);
+  const materialCount = Object.values(inventory.materials || {}).reduce((a: number, b: number) => a + b, 0);
   
   // Calculate essence count
   let essenceCount = 0;