fix clippy on main

[sjwiesman]

Motivation

cargo clippy -p mz-deploy surfaced 7 clippy::disallowed_methods warnings. The crate was calling tokio_postgres query/execute methods directly, which clippy.toml disallows repo-wide in favor of the mz_postgres_util Sql wrappers — these force SQL through the validated Sql type rather than raw strings.

Changes

• src/mz-deploy/Cargo.toml — add mz-postgres-util as a path dependency (single-line Cargo.lock change, no version bumps).
• src/client/connection.rs — the five pass-through wrapper methods (execute, query_one, query, simple_query, batch_execute) now delegate to mz_postgres_util::*. Every call site passes string SQL (no prepared Statement), so the generic ToStatement bound is replaced with &str, wrapped via Sql::raw_unchecked — the sanctioned constructor for internally-assembled, already-trusted SQL.
• src/client/deployment_ops.rs — the two raw Transaction calls (the SUBSCRIBE cursor execute and the FETCH ALL query) go through mz_postgres_util::execute/query; the static "FETCH ALL c" uses Sql::new.
• src/client/errors.rs — add From<mz_postgres_util::PostgresError> for ConnectionError, mapping the Postgres variant back to ConnectionError::Query so the existing rich as_db_error() formatting is preserved.

Testing

No behavioral change; this is a lint-compliance refactor that preserves the existing public API and error formatting of the Client wrapper. cargo clippy -p mz-deploy --all-targets -- -D warnings now passes clean.

🤖 Generated with Claude Code

[def-]

Thanks Seth!