* feat(system): chore(lint): ruff F841 cleanup — 28 unused-variable fixes (2 production dead-code removals + 26 test mock/local cleanups) Co-Authored-By: @devpulse <devpulse@aipass> * feat(system): chore(lint): ruff E741 cleanup — rename ambiguous 'l' to 'line' in 8 comprehensions (3 prod + 5 test) Co-Authored-By: @devpulse <devpulse@aipass> * feat(system): feat(seedgo): add ruff_check as 33rd standard (advisory, branch-level) — DPLAN-0137 Phase 4. Dispatched to @seedgo who built the checker + content + spec + 18 tests, but process ended before committing/replying. Opening PR on their behalf. Integration verified: drone @seedgo audit shows 'Ruff 100%' — auto-discovered, scored, non-blocking. Co-Authored-By: @devpulse <devpulse@aipass> --------- Co-authored-by: @devpulse <devpulse@aipass>