feat: add popup and options pages for LexAI extension

- Created index.html for options page with basic structure.
- Implemented Popup component in Popup.tsx with state management for user input and actions.
- Added index.html for popup page with necessary scripts.
- Included various icon assets for the extension.
- Designed SVG icon for the extension with gradient background and lightning bolt.
- Added multiple screenshots for Chrome Web Store listing.
- Configured WXT for building the Chrome extension with manifest settings.

packages/chrome/wxt.config.ts

@@ -0,0 +1,34 @@
+import { resolve } from 'node:path';
+import { defineConfig } from 'wxt';
+import pkg from './package.json';
+
+export default defineConfig({
+  extensionApi: 'chrome',
+  // Shared-code alias. Deliberately NOT "~" or "@" — WXT force-overwrites those
+  // to srcDir (the project root here), so they cannot point at ./src.
+  alias: {
+    '@lib': resolve(__dirname, 'src/lib'),
+  },
+  modules: ['@wxt-dev/module-react'],
+  manifest: {
+    name: 'LexAI - AI Writing Assistant',
+    description: 'Grammar checking and writing assistance powered by your own LLM API key',
+    // Single source of truth: manifest version always follows package.json,
+    // so a release bump is a one-file edit and versions can never drift.
+    version: pkg.version,
+    icons: {
+      '16': 'icon-16.png',
+      '32': 'icon-32.png',
+      '48': 'icon-48.png',
+      '128': 'icon-128.png',
+    },
+    permissions: [
+      'storage',
+      'activeTab',
+      'contextMenus',
+    ],
+    host_permissions: [
+      '<all_urls>',
+    ],
+  },
+});