refactor: Use package knowledge for configuration scopes (#13457)
### Description
Part 2 of the package/scope knowledge completion stack.
Pass authoritative package and aggregate directories into Turborepo
configuration loading and engine scope validation. Script maps remain an
explicit compatibility payload, and the root Turborepo task namespace
remains available without requiring a root JavaScript package.
### Testing Instructions
- `cargo test -p turborepo-turbo-json`
- `cargo test -p turborepo-engine`
