rscexplorer

Hey! This PR adds the ability to resize the 4 workspace panes (server, client, flight, preview). I've been using the explorer and found it a bit annoying that the panes are fixed at 50/50 - sometimes you want more space for the flight log or to focus on the preview. So I added draggable dividers between them. What this does: 1. You can drag any edge between panes to resize horizontally or vertically 2. There's a small handle in the center where all 4 panes meet - drag that to resize everything at once 3. Double-click any handle to reset back to 50/50 4. Panes are clamped to 20-80% so you can't accidentally collapse them completely Technical notes: 1. Created a new component that uses CSS Grid with custom properties for dynamic sizing 2. Added proper ARIA roles and keyboard accessibility (handles are focusable) 3. No external dependencies - just vanilla React + CSS DEMO:** https://github.com/user-attachments/assets/49c7de00-b591-4a69-8478-3995a20f7bca Let me know if you have any feedback!