* fix: Prevent DrawIO remount and data loss when resizing window across 768px breakpoint
* fix: prevent DrawIO remount and data loss when resizing window
- Move key from ResizablePanelGroup to chat-panel only
- Save diagram to localStorage before breakpoint change
- Restore defaultSize on drawio-panel to prevent layout flash
- Keep save button functionality from main
* fix: reset draw.io ready state on breakpoint change to restore diagram
* fix: skip initial render save and remove console logs
- Add isInitialRenderRef to skip unnecessary save/reset on first render
- Remove console.log statements for production cleanliness
- Add eslint-disable comment explaining loadDiagram dependency
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Co-authored-by: dayuan.jiang <jdy.toh@gmail.com>