chore: enable client-side routing in dev server

Added historyApiFallback to webpack dev server config to properly handle
client-side routing. Without this, refreshing the page on non-root routes
would return 404 errors.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: balzss

packages/__docs__/webpack.config.mjs

@@ -56,6 +56,7 @@ const config = merge(baseConfig, {
       directory: outputPath,
     },
     host: '0.0.0.0',
+    historyApiFallback: true,
     client: {
       overlay: false,
     },