usage related fixes + mysql insert fix

- SQL view is now toggled by default, so export functions are visible
without having to toggle it
- "always show SQL clipboard on export" function is now saved into a
cookie, so if users uncheck it, it remains unchecked even after page
reload
- starting a new query will not ask users anymore if they want to clear
the SQL clipboard or not
- clipboard now can be cleared by a button
- pressing F5 will do nothing if the buttons which call the same
function are disabled
- if the exported entry does not exist in TauriDB, the software will use
an INSERT syntax instead of UPDATE (and ignore checkboxes)
- small bug fix with entry titles on server side