Stability checkpoint stable-v1.0.20 (UI) — post-v1.0.19 wave: security+db+chaos types extracted to sibling files (~210 LOC moved out of components: security 681→547, database 644→599, chaos 632→600). CLAUDE.md updated with B-7 wave landing table (14 file splits, 12 visible). Post-merge main pipelines #359 (security+db) + #361 (chaos) both SUCCESS.