Week counter component

### Description
Implement a Week Counter component that tracks the current week of the semester.

### Tasks
- [ ] Create the basic structure of the Week Counter component.
- [ ] Implement logic to calculate the current week of the semester.
- [ ] Display the current week number prominently.
- [ ] Add a progress bar to represent the progress visually.
- [ ] Style the component to match the overall design of the application.

### Acceptance Criteria
- The Week Counter should accurately display the current week of the semester.
- The component should be visually appealing and consistent with the application's theme.

No files, tests, or entry points are named in the issue. Start by locating the application's existing component structure and semester/date configuration, then define the current-week calculation and visual conventions; done means a themed Week Counter displays the current week and a corresponding progress bar.

Written by the indexing model from the issue text.