chore(DC-162): record grade B (round 3) + sync changelog test count

urn:ump:or2qqhcytp6lfzlyi7xru7hdqy3uar2hbjllsrrbxrbray3c5kpa

CHANGELOG.md

@@ -27,8 +27,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   params URL-encoded. Backend: routes/mcp.js (POST, GET/DELETE 405, /info,
   /connections, /config), src/mcp/mcp-core.js shared by stdio + HTTP,
   stale 1.15.0 version literal removed (reads package.json).
-  57 route+core tests + composition-root e2e proves the mount boots.
+  73 route+core tests (incl. 16-case JSON-RPC boundary matrix) +
+  composition-root e2e proves the mount boots.
   OpenAPI: 4 MCP path entries. status/dist + sw.js regenerated in-tree.
+- **DC-162 judge: grade B (round 3)** urn:ump:or2qqhcytp6lfzlyi7xru7hdqy3uar2hbjllsrrbxrbray3c5kpa
 - **DC-161: Calendar widget + Radicale auto-wiring.** New top-bar calendar widget
   (`status/js/calendar-widget.js`) showing upcoming appointments; settings modal for
   adding CalDAV / ICS-feed sources with a Test-connection probe. Backend: