Every flourish gets its own file, and a workshop to watch them in

The effects move out of Board.svelte into src/fx-sprites/ — one
component per flourish, markup and animation CSS together, so editing
the fireball means opening Fireball.svelte and nothing else. A
registry (index.ts) maps kind to sprite; Board renders through it.
The event mapping stays in fx.ts.

And a viewer: /?fx opens the Flourish Workshop — every sprite on a
labeled parchment tile, replaying on a 2.2-second beat. Under the dev
server, editing any sprite file hot-reloads the gallery mid-loop.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/web/src/fx-sprites/Pow.svelte

@@ -0,0 +1,25 @@
+<script lang="ts">
+  import type { FxOf } from "../fx";
+  import { center } from "./geom";
+  let { fx }: { fx: FxOf<"pow"> } = $props();
+  const c = $derived(center(fx.at));
+</script>
+
+<g class="pow" style={`transform-origin: ${c.x}px ${c.y}px`}>
+  <path d={`M ${c.x} ${c.y - 14} l 4 8 9 -4 -4 9 8 5 -9 3 2 10 -8 -6 -6 8 -1 -10 -10 1 7 -7 -7 -7 10 0 1 -9 6 8 z`} />
+</g>
+
+<style>
+  .pow path {
+    fill: #ffe94d;
+    stroke: #b3372b;
+    stroke-width: 1.6;
+  }
+  .pow { animation: pow-hit 0.5s ease-out forwards; }
+  @keyframes pow-hit {
+    0% { opacity: 0; transform: scale(0.3) rotate(-15deg); }
+    25% { opacity: 1; transform: scale(1.25) rotate(5deg); }
+    55% { transform: scale(1) rotate(0deg); }
+    100% { opacity: 0; transform: scale(1.05); }
+  }
+</style>