When total sum of persisted panel sizes differs from 100, no resize is possible

[tsufiev]

The issue can be easily reproduced by going to https://react-resizable-panels.vercel.app/examples/persistence and manually altering one of panel percentage sizes inside localStorage's value under PanelGroup:sizes:persistence key.

The tricky question here is how does the app come to such a corrupted state in localStorage? Unfortunately I cannot share any insight at the moment. The only thing I know is that several users came to me complaining about inability to adjust panel sizes and the only thing I found in their browsers were those size discrepancies.

[bvaughn]

Fixed in #230