Add Sorting and Filtering Enhancements for DRep Budget Proposal Views

[bosko-m]

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.