Ensure proper tools re-alignment in toolbar
Corrected an issue where tools within the Tool bar were not properly re-aligning when the window was resized. Previously, GtkScrolledWindow's horizontal alignment was set to START, preventing the tools from expanding and filling the available space.
This fix sets the GtkScrolledWindow's horizontal alignment to FILL and enables horizontal expansion for the PopoverBin, which allows the toolbar tools to adapt dynamically to changes in the window size.