Release 0.9.9 collapsed sidebar patch

[ehud-am]

Summary

• clean up collapsed left sidebar to show only one expand control
• fix README logo rendering in both GitHub and GitLocal local Markdown rendering
• bump release metadata to 0.9.9

Validation

• npm run verify
• npm pack --dry-run
• packaging/macos/release/package-app.sh
• packaging/macos/release/test-package.sh
• packaging/macos/release/validate-artifact.sh packaging/macos/release/artifacts/GitLocal-0.9.9-macos.zip
• packaging/macos/release/validate-version-alignment.sh
• packaging/macos/cask/validate-cask.sh packaging/macos/cask/gitlocal.rb
• packaging/macos/cask/test-install-cask.sh packaging/macos/cask/gitlocal.rb packaging/macos/release/artifacts/GitLocal-0.9.9-macos.zip