refactor(specTypeSchema): drop as unknown as casts; add allowlist drift guard#1993

KKonstantinov merged 2 commits intomainmodelcontextprotocol/typescript-sdk:mainfrom

fweinberger/spec-type-schema-followupsmodelcontextprotocol/typescript-sdk:fweinberger/spec-type-schema-followupsCopy head branch name to clipboard