fix: Remove unused variables to resolve ESLint errors

🔧 ESLint Fixes:
- Remove unused 'categoryConfig' variable in Layout.js (line 167)
- Remove unused 'isHome' variable in ToolSidebar.js (line 77)
- Remove unused 'Sparkles' import in tools.js (line 1)

✅ Build Status:
- All ESLint errors resolved
- Build now compiles successfully
- Ready for deployment

📁 Files Modified:
- /src/components/Layout.js - Removed unused categoryConfig for NON_TOOLS
- /src/components/ToolSidebar.js - Removed unused isHome for NON_TOOLS
- /src/config/tools.js - Removed unused Sparkles import

src/config/tools.js

@@ -1,4 +1,4 @@
-import { Edit3, Table, LinkIcon, Hash, Wand2, GitCompare, Type, Home, Sparkles, Zap } from 'lucide-react';
+import { Edit3, Table, LinkIcon, Hash, Wand2, GitCompare, Type, Home, Zap } from 'lucide-react';
 
 // Master tools configuration - single source of truth
 export const TOOL_CATEGORIES = {