Improved rebuild parameter page

[thxwelchs]

The parameter value of parameter pages jelly resource can also find the parameter value's class, including its self class and superclasses.

In the Rebuild Jelly Resource, various plugin parameters that do not exist might be present, but most of them inherit from the upper-level Base parameter types. Therefore, it seems safer to have the default value of the upper parameter type applied when a Jelly fallback occurs.

This is particularly relevant when used with parameters like date-parameter plugin, where an incorrect value (such as the current date, LocalDate.now()) may be set as the default on the rebuild page.

Testing done

mvn clean verify passed

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