chore(tasks): mark yaml-normalization, mcp-batch-cap, cov13, projection-truthfulness completed

tasks/adapters/review-002-yaml-normalization.md

@@ -1,7 +1,7 @@
 ---
 id: review-002-yaml-normalization
 name: YAML input normalization — duplicates, .inf, merge keys, non-string keys (OAI-12)
-status: pending
+status: completed
 depends_on: []
 scope: narrow
 risk: medium
@@ -66,4 +66,8 @@ Keep the walk cheap (one pass, no allocation beyond error messages).
 The alias-bomb/depth bounds are dependency-provided and verified
 working (review 002 re-verified) — do not re-implement them; the task
 is about *semantic* normalization, not resource limits. ADR-051 is the
-decision record to update if the merge-key stance changes behavior.
+decision record to update if the merge-key stance changes behavior.
+
+## Summary
+
+Post-parse YAML normalization at the from_yaml seam: loud duplicate-key rejection (yaml_serde native), merge keys applied (shallow), .inf/.nan + non-representable keys rejected with pointers, scalar keys stringified per YAML 1.2 core schema. Premise correction recorded: serde_json Value itself last-wins on dups - parity contract is YAML-stricter-by-design. ADR-051 section added.