Sidebar was hidden on mobile with no fallback, so users were stuck on
the default view. Add a horizontal tab strip under the header for
mobile viewports and drop the "后台系统设置" button which had no handler
or matching view.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Sets up the basic project files and dependencies for an AI Studio application. Includes README, `.env.example`, `.gitignore`, basic HTML structure, metadata, `package.json`, Vite configuration, and initial React component setup. This commit provides the foundation for running and deploying the AI Studio app locally.