- Replace `$` and `Bun.spawn` with `execa` for process execution
- Swap `Bun.JSONL.parse` for native `JSON.parse` and use `node:readline` for stdin handling
- Pin `@types/bun` to `^1.3.14` for reproducible builds instead of using `latest`
- Update `tsconfig.json` with stricter type-checking flags and reorganize compiler options
- Refactor `initConfig` to DRY up the model default logic and add a null guard before process exit