feat: comprehensive security and architecture improvements

- Add Zod validation schemas with strong password requirements (12+ chars, complexity)
- Implement rate limiting for authentication endpoints (registration, password reset)
- Remove duplicate MetricCard component, consolidate to ui/metric-card.tsx
- Update README.md to use pnpm commands consistently
- Enhance authentication security with 12-round bcrypt hashing
- Add comprehensive input validation for all API endpoints
- Fix security vulnerabilities in user registration and password reset flows

🤖 Generated with [Claude Code](https://claude.ai/code)

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

components/charts/bar-chart.tsx

@@ -61,10 +61,13 @@ export default function ModernBarChart({
       )}
       <CardContent>
         <ResponsiveContainer width="100%" height={height}>
-          <BarChart data={data} margin={{ top: 5, right: 30, left: 20, bottom: 5 }}>
-            <CartesianGrid 
-              strokeDasharray="3 3" 
-              stroke="hsl(var(--border))" 
+          <BarChart
+            data={data}
+            margin={{ top: 5, right: 30, left: 20, bottom: 5 }}
+          >
+            <CartesianGrid
+              strokeDasharray="3 3"
+              stroke="hsl(var(--border))"
               strokeOpacity={0.3}
             />
             <XAxis
@@ -84,14 +87,14 @@ export default function ModernBarChart({
               axisLine={false}
             />
             <Tooltip content={<CustomTooltip />} />
-            <Bar 
-              dataKey={dataKey} 
+            <Bar
+              dataKey={dataKey}
               radius={[4, 4, 0, 0]}
               className="transition-all duration-200"
             >
               {data.map((entry, index) => (
-                <Cell 
-                  key={`cell-${index}`} 
+                <Cell
+                  key={`cell-${index}`}
                   fill={colors[index % colors.length]}
                   className="hover:opacity-80"
                 />