1. Add a search boxer in the left tree view of Playground.
2. Fix some visual bugs of UI.
3. Fix bugs that link failed in QueryProfile view.
4. Fix bugs that cookie is always invalid.
5. Set cookie to HTTP_ONLY to make it more safe.
This is the last PR of proposal #4308
1. Add a new FE config `enable_http_server_v2` to enable new HTTP Server implementation. The default value is false.
2. Add a new FE config `http_api_extra_base_path` so that we can set base path for Frontend UI.
3. Refactor the new HTTP API response body. The return http status code is always 200, and using internal code in response body to indicate the certain error.
A new FE UI interface implemented with React framework.
Need to work with the new Spring framework and RESTful API in #4596.
This is a simple UI for Doris. User can develope their own UI if they want
Proposal #4308
