fix(skills): plan is a decision artifact; progress comes from git (#666)

plugins/compound-engineering/skills/ce-code-review/SKILL.md

@@ -159,7 +159,7 @@ Every review spawns all 4 always-on personas plus the 2 CE always-on agents, the
 The following paths are compound-engineering pipeline artifacts and must never be flagged for deletion, removal, or gitignore by any reviewer:
 
 - `docs/brainstorms/*` -- requirements documents created by ce-brainstorm
-- `docs/plans/*.md` -- plan files created by ce-plan (living documents with progress checkboxes)
+- `docs/plans/*.md` -- plan files created by ce-plan (decision artifacts; execution progress is derived from git, not stored in plan bodies)
 - `docs/solutions/*.md` -- solution documents created during the pipeline
 
 If a reviewer flags any file in these directories for cleanup or removal, discard that finding during synthesis.
@@ -354,7 +354,7 @@ Locate the plan document so Stage 6 can verify requirements completeness. Check
 - Multiple/ambiguous PR body matches -> `plan_source: inferred` (lower confidence)
 - Auto-discover with single unambiguous match -> `plan_source: inferred` (lower confidence)
 
-If a plan is found, read its **Requirements Trace** (R1, R2, etc.) and **Implementation Units** (checkbox items). Store the extracted requirements list and `plan_source` for Stage 6. Do not block the review if no plan is found — requirements verification is additive, not required.
+If a plan is found, read its **Requirements Trace** (R1, R2, etc.) and **Implementation Units** (items listed under the `## Implementation Units` section). Store the extracted requirements list and `plan_source` for Stage 6. Do not block the review if no plan is found — requirements verification is additive, not required.
 
 ### Stage 3: Select reviewers