style: replace static grid with animated grid pattern in chart

Use AnimatedGridPattern from 21st.dev with subtle fading squares.
Scoped to CardContent only so the metric tabs and annotation footer
stay clean.

components/ui/animated-grid-pattern.tsx

@@ -0,0 +1,148 @@
+"use client";
+
+import { useEffect, useId, useRef, useState } from "react";
+import { motion } from "framer-motion";
+
+import { cn } from "@/lib/utils";
+
+interface AnimatedGridPatternProps {
+  width?: number;
+  height?: number;
+  x?: number;
+  y?: number;
+  strokeDasharray?: any;
+  numSquares?: number;
+  className?: string;
+  maxOpacity?: number;
+  duration?: number;
+  repeatDelay?: number;
+}
+
+export function AnimatedGridPattern({
+  width = 40,
+  height = 40,
+  x = -1,
+  y = -1,
+  strokeDasharray = 0,
+  numSquares = 50,
+  className,
+  maxOpacity = 0.5,
+  duration = 4,
+  repeatDelay = 0.5,
+  ...props
+}: AnimatedGridPatternProps) {
+  const id = useId();
+  const containerRef = useRef(null);
+  const [dimensions, setDimensions] = useState({ width: 0, height: 0 });
+  const [squares, setSquares] = useState(() => generateSquares(numSquares));
+
+  function getPos() {
+    return [
+      Math.floor((Math.random() * dimensions.width) / width),
+      Math.floor((Math.random() * dimensions.height) / height),
+    ];
+  }
+
+  // Adjust the generateSquares function to return objects with an id, x, and y
+  function generateSquares(count: number) {
+    return Array.from({ length: count }, (_, i) => ({
+      id: i,
+      pos: getPos(),
+    }));
+  }
+
+  // Function to update a single square's position
+  const updateSquarePosition = (id: number) => {
+    setSquares((currentSquares) =>
+      currentSquares.map((sq) =>
+        sq.id === id
+          ? {
+              ...sq,
+              pos: getPos(),
+            }
+          : sq,
+      ),
+    );
+  };
+
+  // Update squares to animate in
+  useEffect(() => {
+    if (dimensions.width && dimensions.height) {
+      setSquares(generateSquares(numSquares));
+    }
+  }, [dimensions, numSquares]);
+
+  // Resize observer to update container dimensions
+  useEffect(() => {
+    const resizeObserver = new ResizeObserver((entries) => {
+      for (let entry of entries) {
+        setDimensions({
+          width: entry.contentRect.width,
+          height: entry.contentRect.height,
+        });
+      }
+    });
+
+    if (containerRef.current) {
+      resizeObserver.observe(containerRef.current);
+    }
+
+    return () => {
+      if (containerRef.current) {
+        resizeObserver.unobserve(containerRef.current);
+      }
+    };
+  }, [containerRef]);
+
+  return (
+    <svg
+      ref={containerRef}
+      aria-hidden="true"
+      className={cn(
+        "pointer-events-none absolute inset-0 h-full w-full fill-gray-400/30 stroke-gray-400/30",
+        className,
+      )}
+      {...props}
+    >
+      <defs>
+        <pattern
+          id={id}
+          width={width}
+          height={height}
+          patternUnits="userSpaceOnUse"
+          x={x}
+          y={y}
+        >
+          <path
+            d={`M.5 ${height}V.5H${width}`}
+            fill="none"
+            strokeDasharray={strokeDasharray}
+          />
+        </pattern>
+      </defs>
+      <rect width="100%" height="100%" fill={`url(#${id})`} />
+      <svg x={x} y={y} className="overflow-visible">
+        {squares.map(({ pos: [x, y], id }, index) => (
+          <motion.rect
+            initial={{ opacity: 0 }}
+            animate={{ opacity: maxOpacity }}
+            transition={{
+              duration,
+              repeat: 1,
+              delay: index * 0.1,
+              repeatType: "reverse",
+            }}
+            onAnimationComplete={() => updateSquarePosition(id)}
+            key={`${x}-${y}-${index}`}
+            width={width - 1}
+            height={height - 1}
+            x={x * width + 1}
+            y={y * height + 1}
+            fill="currentColor"
+            strokeWidth="0"
+          />
+        ))}
+      </svg>
+    </svg>
+  );
+}