Port remaining lem-repo components into pkg/ml/:
- convert.go: safetensors reader/writer, MLX→PEFT converter
- gguf.go: GGUF v3 writer, MLX→GGUF LoRA converter
- export.go: training data JSONL export with split/filter
- parquet.go: Parquet export with snappy compression
- db.go: DuckDB wrapper for golden set and expansion prompts
- influx.go: InfluxDB v3 client for metrics/status
- ollama.go: Ollama model management (create/delete with adapters)
- status.go: training and generation status display
- expand.go: expansion generation pipeline (Backend interface)
- agent.go: scoring agent with probe running and InfluxDB push
- worker.go: distributed worker for LEM API task processing
Adds parquet-go and go-duckdb dependencies.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>