fix: preserve tsconfig jsx emit in babel builds

[wanxiankai]

Summary

Fixes #678.

Preserves JSX during Bob's Babel builds when the project tsconfig.json sets compilerOptions.jsx to preserve or react-native.

Why

Libraries that rely on preserved JSX, for example to use a custom jsxImportSource, currently get their TSX output transformed through @babel/preset-react anyway. That turns JSX into react/jsx-runtime calls even when TypeScript config asks to keep JSX syntax.

What changed

• Reads tsconfig.json with TypeScript's config parser during Babel compilation.
• Passes a preserveJSX caller flag to Bob's Babel preset when JSX emit is preserve or react-native.
• Skips @babel/preset-react in that mode so @babel/preset-typescript can strip types while leaving JSX intact.
• Adds regression coverage for both jsx: "preserve" and jsx: "react-native".

Test plan

• YARN_GLOBAL_FOLDER=/tmp/codex-yarn-global-builder-bob yarn workspace react-native-builder-bob test
• YARN_GLOBAL_FOLDER=/tmp/codex-yarn-global-builder-bob yarn lint
• YARN_GLOBAL_FOLDER=/tmp/codex-yarn-global-builder-bob yarn typecheck
• YARN_GLOBAL_FOLDER=/tmp/codex-yarn-global-builder-bob yarn workspace react-native-builder-bob prepare
• git diff --check