Fix Saving Window Width

[onesounds]

What's the PR

• Fixes an issue where the window width is not saved and comes out as the minimum size after merging the window resize PR.

What Happens?

• Basically, We save the settings at onclosing() timing. However, in this case, the window has already disappeared during closing, and it seems to be treated as if the window size has been reduced to minimum size, and this setting is updated to settings.windowsize. The window width becomes zero and is saved.
• Previously, We didn't notice the bug because "min-width" was equal to width. (It was set this way to prevent mouse resizing.) so If we tried close -> window disappeared -> reduced window size to min-width (actually equal to width) in onclosing() timing -> save width. As a result, the normal width was saved because the minwidth was equal to the width.

My Solution

• We need to set this value aside and update it at the onclosing() timing,
• Or change the save setting timing to a different point in time.

My choice is first. (This is the best way to reduce code change.) Instead of putting code in each function, we put the window size into a specific variable whenever the window size changes and only save it when the window is closed. Better logic or simple workarounds are welcome. This is the cleanest way I could do it.