TOC navigations should be recorded in history

Currently, the TOC #42 navigations do not go through the Qt system and use Javascript to scroll directly. It would be great to have an in-page history, where the history records those actions but sends them to Javascript for scrolling instead of refreshing the current page to the URL.

Note that if a page is refreshed, all DOM states are also reset, which is not what we want. This is the reason why we cannot use setUr to navigate to TOC entries.