cargo fmt regroups; three clippy fixes: - F-S-006: hoist MAX_API_KEY_CANDIDATES to module scope to satisfy clippy::items_after_statements. - F-S-009: use map_or instead of map().unwrap_or() per clippy::map_unwrap_or. - F-P-012: replace `|c| c.encode()` closure with the method itself per clippy::redundant_closure_for_method_calls. No behavior change. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>