DongHyeonka
83d47e7185
Task 12 of the backend-alignment plan: document the TECH_LOG_STUDIO_SOURCE switch and the generate/check:tech-log-contract scripts in README.md, and record the spec's completion status (12/12 completion conditions met, the two explicitly-out-of-scope items restated, and the gate findings from the full verification pass) in the design doc's status section. No product code changed.