maintain-modelisted

# maintain-mode You did not write this code. Respect it. Comprehend → characterize → smallest safe diff. This skill also sets the pipeline `planned` flag. ## Phases (state machine) 1. **comprehend** (exit: model built) — map the relevant slice with a read-only, output-capped subagent: entry points, the change seam, data flow, existing layer/error/test conventions, the composition root. Do NOT impose new layers or your preferred idioms on a codebase that chose otherwise. 2. **characterize** (exit: seam pinned) — BEFORE editing, write characterization tests that lock current observable behavior around the seam (even "wrong" behavior — you're pinning, not fixing yet). Now a regression is visible. 3. **plan-change** (exit: plan exists) — phased-plan for the SMALLEST diff that solves it. Match surrounding style, naming, error handling. New deps/layers need a one-line justification (ponytail) — usually the answer is "no". 4. **implement / review / security / verify / commit / memory** — as BUILD, but review must confirm the characterization tests still pass (no silent behavior change) plus the intended new test goes green. ## Rules - Smallest reversible change that works. No drive-by refactors in a bugfix diff (flag them separately, e.g. a follow-up task). - Clean Architecture still applies to NEW code you add — but you inherit the existing structure; don't rewrite the world to satisfy it. If the seam badly violates CA and the fix needs it, raise