[tracking issue] delta kernel write path

[zachschuermann]

Tracking issue for write support in delta_kernel. Will be updating with PRs/links as we go!

• stage 0: blind append support
  • prefactor: move transaction module into actions/ and rename to set_transaction #386
  • transaction/commit flow #378
  • append transaction data path #390
• stage 1: FFI (for blind append)
  • transaction/append FFI #391
  • duckDB integration
• stage 2: create table, checkpointing, better conflict resolution, stats collection
  • create table API
  • checkpointing API
  • conflict detection and automatic retries
  • stats collection
• stage 3: follow-ups
  • make write_json_file streaming write
  • concurrent parquet writes in default parquet handler