[6.x] Modernize garnish

packages/craftcms-garnish/.gitignore

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+/dist
+/node_modules
+/coverage
+/storybook-static

packages/craftcms-garnish/.nvmrc

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+v22

packages/craftcms-garnish/.storybook/main.ts

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+import type {StorybookConfig} from '@storybook/html-vite';
+
+import {dirname} from 'path';
+import {fileURLToPath} from 'url';
+
+/**
+ * Resolve the absolute path of a package. Needed in monorepos so Storybook finds
+ * the hoisted addons/framework regardless of where node_modules ends up.
+ */
+function getAbsolutePath(value: string): string {
+  return dirname(fileURLToPath(import.meta.resolve(`${value}/package.json`)));
+}
+
+/**
+ * Storybook config for @craftcms/garnish.
+ *
+ * Garnish widgets are imperative (`new Modal(container)`, `new DisclosureMenu(trigger)`)
+ * operating on plain DOM — NOT web components — so we use the `html-vite` renderer
+ * (cp uses `web-components-vite`). Each story's `render()` returns an `HTMLElement`
+ * in which the Garnish class is instantiated against the REAL source under `../src`.
+ */
+const config: StorybookConfig = {
+  stories: ['../stories/**/*.stories.@(ts|mdx)'],
+  addons: [
+    getAbsolutePath('@storybook/addon-docs'),
+    getAbsolutePath('@storybook/addon-a11y'),
+    getAbsolutePath('@storybook/addon-themes'),
+  ],
+  framework: {
+    name: getAbsolutePath('@storybook/html-vite'),
+    options: {},
+  },
+};
+export default config;