chore: isolate build artifacts and storybook smoke infra

apps/docs/.storybook/main.ts

@@ -1,7 +1,16 @@
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
 import tailwindcss from "@tailwindcss/vite";
 import type { StorybookConfig } from "@storybook/react-vite";
 import { mergeConfig } from "vite";
 
+const storybookConfigDir = path.dirname(fileURLToPath(import.meta.url));
+const storybookCacheDir = path.resolve(
+  storybookConfigDir,
+  "../../../.artifacts/cache/storybook/vite"
+);
+
 const config: StorybookConfig = {
   stories: ["../src/**/*.stories.@(ts|tsx)"],
   addons: [
@@ -15,6 +24,7 @@ const config: StorybookConfig = {
   },
   async viteFinal(config) {
     return mergeConfig(config, {
+      cacheDir: storybookCacheDir,
       plugins: [tailwindcss()]
     });
   }