fix(parquet/pqarrow): propagate level builder errors

[fallintoplace]

Summary

• return errors from multipath level builder construction instead of reporting a successful column write
• release builders created for earlier chunks when a later chunk fails
• release partially initialized builder state on visitor errors
• leave the physical column position unchanged after builder construction fails

Testing

• go test ./parquet/pqarrow

The regression test uses a valid dictionary chunk followed by a dictionary containing a null, which reaches the previously swallowed error path, verifies checked allocator cleanup, and successfully retries the same physical column with supported data.