refactor: cleanup codebase — remove hydration guards, extract constants, fix bugs

src/components/game/tabs/AchievementsTab.tsx

@@ -1,6 +1,6 @@
 'use client';
 
-import { useState, useMemo, useEffect } from 'react';
+import { useState, useMemo } from 'react';
 import { useCombatStore } from '@/lib/game/stores';
 import {
   ACHIEVEMENTS,
@@ -164,14 +164,8 @@ function CategorySection({
 
 export function AchievementsTab() {
   const achievements = useCombatStore((s) => s.achievements);
-  const [mounted, setMounted] = useState(false);
   const [collapsedCategories, setCollapsedCategories] = useState<Record<string, boolean>>({});
 
-  useEffect(() => {
-    // eslint-disable-next-line react-hooks/set-state-in-effect
-    setMounted(true);
-  }, []);
-
   const byCategory = useMemo(() => getAchievementsByCategory(), []);
   const categories = useMemo(
     () => Object.keys(byCategory).sort(),
@@ -188,14 +182,6 @@ export function AchievementsTab() {
     }));
   };
 
-  if (!mounted) {
-    return (
-      <div className="flex items-center justify-center p-8 text-gray-500">
-        Loading achievements…
-      </div>
-    );
-  }
-
   return (
     <DebugName name="AchievementsTab">
       <div className="space-y-4">