feat(datagen): add dataset generation CLI with sharding and checkpointing
- Add solver/datagen/dataset.py with DatasetConfig, DatasetGenerator,
ShardSpec/ShardResult dataclasses, parallel shard generation via
ProcessPoolExecutor, checkpoint/resume support, index and stats output
- Add scripts/generate_synthetic.py CLI entry point with Hydra-first
and argparse fallback modes
- Add minimal YAML parser (parse_simple_yaml) for config loading
without PyYAML dependency
- Add progress display with tqdm fallback to print-based ETA
- Update configs/dataset/synthetic.yaml with shard_size, checkpoint_every
- Update solver/datagen/__init__.py with DatasetConfig, DatasetGenerator
exports
- Add tests/datagen/test_dataset.py with 28 tests covering config,
YAML parsing, seed derivation, end-to-end generation, resume,
stats/index structure, determinism, and CLI integration
Closes #10
forbes-0023
f29060491e