Add loading skeleton state to VisionPanel while analyzing

[alimaandev]

Summary

desktop/src/components/sidebar/VisionPanel.tsx has capture buttons for Screen and Camera. While �nalyzing is true it only shows a text label (\Analyzing.) with no visual loading state.

Goal

When �nalyzing is true, show a Skeleton block (reuse desktop/src/components/common/Skeleton.tsx) in place of the result area, and disable the capture buttons.

Tasks

• Add a loading branch in VisionPanel's render for the �nalyzing state
• Disable the two capture buttons while analyzing
• Reuse the existing Skeleton component — do not introduce a new loader

Acceptance criteria

• Buttons are disabled + visually dimmed while �nalyzing
• A skeleton placeholder replaces the result area during analysis
• Existing behavior unchanged when not analyzing

Labels

good first issue, help wanted