Add feedback form and progress indicator

[ewalid]

Summary

Add a user feedback flow and a translation progress indicator to improve usability and visibility into long-running translation operations.

Changes

• Feedback

  • Add FeedbackModal component to capture user feedback.
  • Add Feedback.css and related styling for the feedback UI.
  • Wire feedback entry point into existing layout (e.g. footer / layout components).
  • Extend shared types in frontend/src/types/index.ts to support feedback data structures.
  • Update frontend/src/api/client.ts and src/rosetta/api/app.py to send feedback data to the backend.

• Progress indicator

  • Add ProgressIndicator component and Progress.css to display translation progress.
  • Add SheetSelector for choosing sheets during translation.
  • Update TranslateForm and Translate feature index to integrate progress indicator and sheet selector.
  • Tweak Translate.css styling to accommodate progress UI and layout changes.

• UI/UX & layout

  • Adjust FileDropzone behavior and styling to work well with the new flow.
  • Update Layout.css, Footer, and Timeline to ensure consistent styling and surface the new features.
  • Minor refactors in useFileUpload to support progress-aware uploads.