feat(cli): parallel catalog validation and fleet rollup

CHANGELOG.md

@@ -6,6 +6,11 @@ All notable changes to SkillEvaluator are documented in this file.
 
 ### Added
 
+- Catalog validation now writes `catalog-summary.json` at the reports root with
+  per-skill pass/fail status, optional severity rollups from child JSON reports,
+  and paths to per-skill report directories.
+- Catalog `validate` accepts `--workers N` to validate skills in parallel child
+  processes (default 1 preserves the serial per-skill pipeline view).
 - `SKILL_EVAL_MODEL_CATALOG_ALLOW_HTTP_HOSTS` names hosts whose model catalog may
   be read over plain HTTP. Catalog reads still require HTTPS for every other
   non-loopback host. Entries match one whole host as written, with no name