Clean up shortcuts without actions and load all shortcuts as late as possible

[krasko78]

Resolves: #29054

A couple of commits in the PR:

1. Renames one shortcut's action and deletes the rest of the shortcuts for which no corresponding actions exists. This removes all warnings about invalid actions except for the ones related to plugins.

2. The second group of warnings about invalid actions in the form action://extensions/... is dealt with in the second commit. Those actions are added when ExtensionsModule's onDelayedInit() executes which currently happens after the ShortcutsModule has loaded all the shortcuts. As a result, the loading of the shortcuts does not find the actions for the extensions. The solution I see and that I've implemented here is to move the ShortcutsModule at the end of the modules list and the loading of the shortcuts in a new onDelayedInit() method of the ShortcutsModule. Although the order of the modules should not matter, this is not really the case and has produced various issues, so moving the ShortcutsModule further down the list is a bit of a risky change and needs to be tested well. In my testing I looked at the uses of shortcutsRegister()->shortcut and shortcutsRegister()->shortcuts() by any code that executes before ShortcutsModule::onDelayedInit() and here's what I found:

• UiActionsRegister::updateShortcuts and UiActionsRegister::updateShortcutsAll()
• TextInputModel::loadShortcuts()
• LayoutPanelTreeModel::addInstrumentsKeyboardShortcut()
• ShortcutsInstanceModel::doLoadShortcuts()

and then ShortcutsModule::onDelayedInit() executes. It calls ShortcutsRegister::reload which loads all shortcuts and at the end emits m_shortcutsChanged. Luckily, all classes above - UiActionsRegister, TextInputModel, LayoutPanelTreeModel and ShortcutsInstanceModel- have subscribed to this signal and reload their shortcuts when they are notified about it. So theoretically all shortcuts should continue to work. I didn't find issues in my testing but again we need to test this well. Whoever reviews this PR (I suppose Igor) - let me know what you think.

I spotted a small issue in TextInputModel::loadShortcuts() which is fixed in the second commit as well.

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• The code compiles and runs on my machine, preferably after each commit individually
• I created a unit test or vtest to verify the changes I made (if applicable)

[krasko78]

@DmitryArefiev @zacjansheski In addition to verifying the warnings are gone, can you please do some shortcuts testing to ensure shortcuts work as before? Any shortcuts you can think of - menus, toolbars, percussion panel, plugins, etc. Many thanks!