Fix tab order in Render dialog
When pressing Tab in the Render dialog, focus jumped through fields randomly instead of following a logical sequence.
The root cause was that the <tabstops> block in renderwidget_ui.ui was both incomplete (around 10 widgets missing entirely) and misordered (widgets from all three tabs mixed together).
This MR reorders the existing entries and adds the missing widgets so Tab follows the visual layout: output file → presets → render range → options → video settings → audio → quality → encoder → export options → action buttons, then Job Queue and Scripts tabs.
One known remaining issue: video_box (the Video groupbox checkbox) appears at position 60 due to Qt's handling of checkable QGroupBoxes inside a QScrollArea, this cannot be fixed via the .ui file alone.