Add year filter for papers

Hi, for some tasks there are no reliable benchmarks yet, for example 3D generation. In these cases, users often try to find the best open-source models from the current year or the last couple of years.

Right now this is hard to do on Papers With Code. For example, in 3D generation, the current flow is:

- Trending often shows older papers, such as TRELLIS from 2024
- Newest returns many unrelated or random papers
- Most cited mostly surfaces older work

It would be very useful to have a filter by publication year, for example 2026 / 2025 / 2024, so users can quickly find recent papers and models, especially when they are not included in benchmarks yet.