Add Sorting and Filtering Enhancements for DRep Budget Proposal Views

## Description
Enhance sorting and filtering options in the **Budget Proposals** section to support **DRep-specific views**.
New capabilities should allow users to:
- Quickly filter for **proposals not yet viewed**.
- Filter or sort by **voting status** (e.g., "Not Voted", "Voted Yes", etc.).

## Acceptance Criteria
- [ ] New filter option to show **only proposals the connected DRep hasn’t voted on**.
- [ ] New sort option based on **voting status** or **last viewed**.
- [ ] Filters work in combination with existing categories and sorting.