support query runtime limits

[cldellow]

SQLite's Python interface supports interrupting long-running queries. DuckDB's C API supports this, too, but it has not yet been exposed to the Python API. See duckdb/duckdb#5938 and duckdb/duckdb#3749

A really brutal workaround: DuckDB will respond to signals... could we temporarily install a signal handler that prevents SIGINT from killing the server, but lets it percolate through to DuckDB to interrupt? That feels fragile and complex, might be easier to learn how to patch DuckDB

[curiousleo]

interrupt() is now supported in DuckDB's Python API: duckdb/duckdb#7895.
This change was released in version 0.9.0: https://github.com/duckdb/duckdb/releases/tag/v0.9.0