bug(webui): flex columns (e.g. Connection string) cannot be resized and expand/shrink unexpectedly

[mohamadyasser118]

In the Sources grid, the Connection string column cannot be resized by
dragging, it snaps back. When other columns are resized, Connection string
expands or shrinks unexpectedly to fill remaining space even after the user
has tried to set a fixed size.

The expected behaviour is that the Connection string should be resizable by dragging, And It should only expand/fill space until the user explicitly resizes it, After resizing, it should stay at the user-set width.

bug.mp4