The navigate event is not cancellable, as it is fired after the UI has started changing. Its purpose is to be used to interaction with other widgets (datasources) on the page.
What you can do to prevent users from nagivating is to add the following CSS rule to hide the navigation arrows....
.k-calendar .k-header .k-link
...and execute the following script after Calendar initialization in order to remove click event bindings:
cancellables = $(
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