FEAT: cohere rerank 3 model added

[Yash-1511]

Description

Added cohere rerankenglish v3 and rerank multilingual v3.

Fixes # (issue)

Type of Change

Please delete options that are not relevant.

• [x] New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Manual testing with some documents.

Suggested Checklist:

• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] My changes generate no new warnings
• [x] I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods