refactor(export): built-in package for assets export

1. use built-in assets package to support html export
2. improve markdown export

packages/cli/assets/export-html/esbuild.config.mjs

@@ -0,0 +1,27 @@
+import { join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { dirname } from 'node:path';
+
+const assetsDir = dirname(fileURLToPath(import.meta.url));
+const srcDir = join(assetsDir, 'src');
+
+export const buildConfig = {
+  entryPoints: [join(srcDir, 'main.tsx')],
+  bundle: true,
+  minify: true,
+  write: false,
+  outdir: join(assetsDir, 'dist'),
+  platform: 'browser',
+  format: 'iife',
+  target: ['es2018'],
+  jsx: 'automatic',
+  legalComments: 'none',
+  loader: {
+    '.ts': 'ts',
+    '.tsx': 'tsx',
+    '.js': 'jsx',
+    '.jsx': 'jsx',
+    '.css': 'css',
+    '.svg': 'text',
+  },
+};