Add per-partition streaming sync and hybrid query architecture
Partitioned sync: iterates day-by-day instead of loading full dataset.
Each partition: query BQ -> stream to disk -> free RAM. Peak ~50 MB.
New helpers: _sync_single_partition, _cleanup_old_partitions, _generate_partition_dates.
Config: added partition_column_type (DATE/TIMESTAMP/DATETIME), query_mode (local/remote/hybrid).
DuckDB manager: hybrid architecture support (local Parquet + remote BQ tables).
Data sync: skips remote tables, filters by query_mode.
Tests: 113 passing (adapter, client, config, data_sync, duckdb_manager).