fix: build and size limit

[joepegler]

PR-Codex overview

This PR updates project configuration files and removes size-limit configuration for packages/core/index.ts.

Detailed summary

• Updated tsconfig/tsconfig.json to set rootDir to "../packages/core"
• Removed size-limit configuration for packages/core/index.ts
• Added new size limit configurations in .size-limit.json for different core modules
• Updated tsconfig/tsconfig.base.json with changes to lib and moduleResolution properties

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