Function insert_table 

pub fn insert_table(
    db_context: &DbContext,
    event_hub: &Arc<EventHub>,
    undo_redo_manager: &mut UndoRedoManager,
    position: i64,
    rows: i64,
    columns: i64,
) -> Result<InsertTableResult>

Insert a rows x columns table at position using entity controllers.

Creates the Table, one Frame+Block+EmptyElement per cell, and adjusts document_position for all subsequent blocks.