Always do deep copy of parameters initial values before using them

[#62719326]

Otherwise, if initial value is an object or array, all updates to
parameter value will be shared with its initial value!

This issue was visible in one of the interactives where parameters
were retained because of that (what was causing model divergence).
Display help tips only once during interactive lifetime

[#62719326]

Previously help tips could be in theory displayed after each model
reload (assuming that Interactive JSON would change, e.g. due to
parameters initial values update).