server : implement json-schema-to-grammar.mjs & add grammar param in the UI (#2588)

* server : implement json-schema-to-grammar.mjs by follow python impl

* server : add grammar support in chat.mjs

* server : implement grammer param in the UI

* server : generate .hpp

* server : remove trailing whitespaces

* server : generate .hpp

* server : fix sort of prop pairs

* server : optimize regex & iteration