fix: Typescript schema types - move object types to Record<string, unknown> (modelcontextprotocol#2139)

* typescript types - move object types to Record<string, unknown>

* prettier fix

* draft schema regenerate

* md schema regenerate

* introduce JSONObject

* prettier fix

* Update schema/draft/schema.ts

Co-authored-by: Jonathan Hefner <jonathan@hefner.pro>

* regenerated schema

* regenerated mdx

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Co-authored-by: Jonathan Hefner <jonathan@hefner.pro>

Author: KKonstantinov