Add support to write deephaven tables to iceberg

[malhotrashivam]

The spec is being developed along with the development work but at a higher level, the decided APIs look like:

1. void append(Tables...) or appendDataFiles/appendTables: writes tables to data files 1:1, does a transaction to add new data files
2. void overwrite(Tables...) : writes tables to data files 1:1, does a transaction to remove all data files and add new ones
3. List<URI> write(Tables…) : writes tables to data files 1:1, does not put anything in transaction

An important requirement is that we need to persist the Iceberg schema element field-ids into the parquet schema Type field_id field, to map iceberg columns to parquet columns.

[devinrsmith]

We should also see if there is any specific guidance on metadata we should be writing down; in the case of writing a pyarrow table using pyiceberg, we've noticed that the metadata key ARROW:schema contains the arrow schema; in the case of pyspark, it wrote a metadata key iceberg.schema that contains the iceberg schema.