Meta-guide + router for documentation: the two branches (docs-product for 'why/what', docs-project for 'how'), the phase order, completeness levels L1/L2/L3, and the completeness checklist. Load a branch directly when the task is clearly product or engineering; load this skill for the big picture, ordering and completeness gates. Triggers: 'документация', 'набор документации', 'каталог документов', 'документация структура', 'полная документация', 'docs catalog', 'documentation structure', 'какую документацию писать'.
