Part 1. Cleaning up events course_module_viewed and course_module_instance_list_viewed

In /mod/xxx/view.php we are triggering event course_module_viewed extending \core\event\course_module_viewed

$event = \mod_xxx\event\course_module_viewed::create($params);

Sometimes we add record snapshots, sometimes not. Let's agree that we always add snapshot of course and course_modules table and also module table if it is available.

Also mod_forum defines it's own class 'forum_viewed', workshop has some special class for instance view

Part 2. Make sure that object passed to add_record_snapshot() has all necessary fields