SubMiner/changes/2026-03-27-task-238.6-main-runtime-refactor.md

type: internal area: runtime

• Extracted remaining inline runtime logic from src/main.ts into dedicated runtime modules and composer helpers.
• Added focused regression tests for the extracted runtime/composer boundaries.
• Updated task tracking notes to mark TASK-238.6 complete and confirm follow-on boot-phase split can be deferred.