feat(storybook): configure storybook and write stories for UI components

.gitignore

@@ -84,4 +84,6 @@ coverage/
 *.p12
 .cache/
 .temp/
-.tmp/
+.tmp/
+*storybook.log
+storybook-static

frontend/.storybook/main.ts

@@ -0,0 +1,17 @@
+import type { StorybookConfig } from '@storybook/react-vite';
+
+const config: StorybookConfig = {
+  "stories": [
+    "../src/**/*.mdx",
+    "../src/**/*.stories.@(js|jsx|mjs|ts|tsx)"
+  ],
+  "addons": [
+    "@chromatic-com/storybook",
+    "@storybook/addon-vitest",
+    "@storybook/addon-a11y",
+    "@storybook/addon-docs",
+    "@storybook/addon-mcp"
+  ],
+  "framework": "@storybook/react-vite"
+};
+export default config;

frontend/.storybook/preview.tsx

@@ -0,0 +1,21 @@
+import type { Preview } from '@storybook/react-vite'
+
+const preview: Preview = {
+  parameters: {
+    controls: {
+      matchers: {
+       color: /(background|color)$/i,
+       date: /Date$/i,
+      },
+    },
+
+    a11y: {
+      // 'todo' - show a11y violations in the test UI only
+      // 'error' - fail CI on a11y violations
+      // 'off' - skip a11y checks entirely
+      test: 'todo'
+    }
+  },
+};
+
+export default preview;

frontend/eslint.config.js

@@ -1,22 +1,22 @@
+// For more info, see https://github.com/storybookjs/eslint-plugin-storybook#configuration-flat-config-format
+import storybook from "eslint-plugin-storybook";
+
 import js from '@eslint/js'
 import globals from 'globals'
 import reactHooks from 'eslint-plugin-react-hooks'
 import reactRefresh from 'eslint-plugin-react-refresh'
 import tseslint from 'typescript-eslint'
 import { defineConfig, globalIgnores } from 'eslint/config'
 
-export default defineConfig([
-  globalIgnores(['dist']),
-  {
-    files: ['**/*.{ts,tsx}'],
-    extends: [
-      js.configs.recommended,
-      tseslint.configs.recommended,
-      reactHooks.configs.flat.recommended,
-      reactRefresh.configs.vite,
-    ],
-    languageOptions: {
-      globals: globals.browser,
-    },
+export default defineConfig([globalIgnores(['dist']), {
+  files: ['**/*.{ts,tsx}'],
+  extends: [
+    js.configs.recommended,
+    tseslint.configs.recommended,
+    reactHooks.configs.flat.recommended,
+    reactRefresh.configs.vite,
+  ],
+  languageOptions: {
+    globals: globals.browser,
   },
-])
+}, ...storybook.configs["flat/recommended"]])