Refactored `loadTorchConfig` to support dependency injection for `fs`, enabling true unit tests without disk I/O. Added comprehensive unit tests in `test/torch-config-unit.test.mjs`.
- Refactored `loadTorchConfig` to accept optional `fileSystem` argument.
- Created `test/torch-config-unit.test.mjs` with mocked fs tests.
- Verified existing tests pass.
Co-authored-by: PR0M3TH3AN <[email protected]>