Refresh settings panel after save

[Hanjo92]

Summary

• Re-render the Git Roast settings panel after successful saves and key clears.
• Persist a saved status message in the refreshed HTML so the save action is visible immediately.
• Write VS Code setting updates sequentially and add regression coverage for the save refresh flow.
• Bump the extension package to 0.0.4 and rebuild the VSIX.

Verification

• npm run check
• npm run package

Fixes #23