Stability and Quality improvements

This release includes additional search retrievers (Arxiv and more!), and some important stability and quality improvements from improved research quality to UX/UI.

What's Changed

• chore: Update retrievers imports by @0x11c11e in #631
• Correct issue #623 where references from proir runs may remain. by @adrianhensler in #632
• Adding Arxiv Search by @Ayman-Ameen in #543
• Support langchain documents by @hslee16 in #630

New Contributors

• @0x11c11e made their first contribution in #631
• @adrianhensler made their first contribution in #632
• @Ayman-Ameen made their first contribution in #543
• @hslee16 made their first contribution in #630

Full Changelog: v0.2.7...v0.2.8