test: Port final 2 prysk tests to Rust (100% complete) (#12068)
## Summary
- Ports the last 2 prysk tests: `lockfile-aware-caching/new-package.t`
and `other/turbo-trace.t`.
- Also adds Windows parity for find-turbo tests (echo_args.exe placement
+ NTFS junction setup).
- **Zero `.t` files remain.** Full prysk-to-Rust migration is complete.
8 new test functions:
- `lockfile_new_package_test.rs` (1 test) — adds a new pnpm package,
runs `pnpm install`, verifies only the new package appears in `[HEAD]`
git filter.
- `turbo_trace_test.rs` (7 tests) — file path queries, dependency
tracing, circular deps, invalid imports with errors, AST queries, and
depth-limited dependency traversal.
