feat(frontend): price-chart intro sweep (line + crosshair draw left→right) + remove tooltip price box

frontend/app/globals.css

@@ -405,6 +405,18 @@ code {
   animation: gauge-sweep 800ms cubic-bezier(0.22, 1, 0.36, 1) both;
 }
 
+/* Price-chart intro draw — the line + fill are revealed left→right by
+ * Recharts' OWN area-draw animation (the component sets `isAnimationActive` +
+ * ease-out on a sweep remount), and a self-drawn crosshair overlay rides the
+ * curve left→right in lockstep (rAF in PriceHistoryChart.tsx). This replaced an
+ * earlier clip-path-on-the-wrapper approach, which also revealed the X-axis +
+ * date labels — the user wanted those to stay PUT. Recharts animates only the
+ * `.recharts-area` layer (a sibling of `.recharts-xAxis`), so the axis no
+ * longer moves. No CSS keyframe is needed here anymore; the animation is
+ * JS-driven and reduced-motion is handled in the component (skip the rAF + pass
+ * isAnimationActive=false), so SSR / no-JS / reduced-motion show the full chart
+ * immediately. */
+
 /* Hover lift — table rows / cards rise a hair on hover. Kept tiny
  * (1px) + fast so it reads as "alive" not "bouncy"; pairs with the
  * existing slate hover-bg. transform ONLY (Motion Rule 1) — no