* refactor(ci): update deploy permissions and steps for gh pages

- Changed permissions for contents to read.
- Added environment name for GitHub Pages deployment.
- Updated deployment steps to use actions/upload-pages-artifact and actions/deploy-pages.

* chore(deps): update flutter sdk version to ^3.44.5

- Updated the flutter sdk version in pubspec.yaml for the example app.
- Updated sdk version in tools/pubspec.yaml to ^3.12.2.