* use `ctx` as name instead of `project_repository` to make lines shorter
and more readable. This could be done everywhere once the type-name changes
as well.
* Where possible, avoid using `&self` for `VirtualBranchActions` as there is no state.
For now I avoided to remove its usage as field in the filesystem monitor.
* Use a more modern way to use state in `tauri` commands.
* Add the `Ext` suffix to what clearly is extension traits.
Further to the move - the VirtualBranchesExt trait creates a dependency towards gitbutler-project. The gitubler-branch crate doesn't have such dependency so i deemed it undesirable to introduce it just for a convinience method.
(Separately added an extention in gitbutler-virtual-actions since it already depends on project and to create a smaller diff)
