feat(toolbar): overhaul repository action bar UI and status display

This refactors the entire appearance and structure of the repository toolbar, modernizing its layout and improving visual consistency across different states. The component now dynamically displays remote tracking information (ahead/behind) directly on Pull and Push buttons for immediate user feedback.

- Implemented a comprehensive CSS overhaul using grid and flexbox for better responsiveness.
- Added support for German localization within the toolbar actions.
- Enhanced visibility of sync status by displaying commit counts next to pull/push buttons.

src/App.svelte

@@ -3604,8 +3604,11 @@
         hasRepository={workspaceActive}
         {isBusy}
         {operation}
+        ahead={status?.ahead ?? 0}
+        behind={status?.behind ?? 0}
         {autoRefreshEnabled}
         {autoRefreshInFlight}
+        language={appLanguage}
         onFetch={fetchRepo}
         onPull={pullRepo}
         onPush={pushRepo}