[Task] Create new NEAR AI Docs site #604

Background

NEAR AI has a new offering (NEAR AI Cloud) that focuses on hosting open source models in TEEs. The old offering of an Agent SDK / Agent Cloud has been deprecated and no longer supported. The current docs.near.ai sourcecode is located in the /nearai monorepo and should be extracted from this deprecated project. Additonally, we should create a fresh docs site with information focusing on NEAR AI's new offering to mitigate product confusion.

Acceptance Criteria

• Create new docusarus site in a fresh repo within NEAR AI GH org
• Migrate all relevant AI Cloud docs from the old site to the new one
• Enhance content / branding of site
• Audit all articles for accuracy
• Ship new docs site to docs.near.ai