Files where inline tests crowded out production code (test/prod ratio
≥ 0.8) move to sibling files via `#[path]`. Files where production
dominates (query_input.rs, schema_plan.rs) stay inline — extracting
would add noise, not reduce it.
- ir/lower.rs: 1239 → 577 lines (ratio 1.15)
- catalog/mod.rs: 594 → 326 lines (ratio 0.83)
- query/lint.rs: 562 → 314 lines (ratio 0.80)
catalog/tests.rs uses the shorter name since it's inside a module
directory (no ambiguity with filename).
All 229 compiler tests green, identical count to before.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
