Modulize Query Editor query module state

The query module state needs to be split into smaller modules so that new features can be implemented and maintained easier.
This is required to make query tabs in a worksheet, so it blocks MXS-4025.
In addition, to save and load .sql files in IDE, it's technically possible to implement it, but from the UX point of view, with the current design, when loading a file to the editor, there is no good way to show the name of the loaded file. By having a query tab inside a worksheet and using the loaded file name as that query tab name, it explicitly tells which file is loaded. So then MXS-4025 blocks MXS-3723.