chore(DC-167): record grade B (round 11) in changelog

urn:ump:kfn7m6vzd4ias2u5ghg62hvoug3j2y2gmturnytdz4g4od35hx4a

CHANGELOG.md

@@ -9,6 +9,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- **DC-167 judge: grade B (round 11)** urn:ump:kfn7m6vzd4ias2u5ghg62hvoug3j2y2gmturnytdz4g4od35hx4a
+- **DC-167: CalDAV default-namespace multistatus fix (Radicale silent
+  zero-events).** extractCalendarsAndEvents required a namespace prefix on
+  <response>; Radicale emits bare <response> (default DAV ns) so every entry
+  was silently dropped — REPORT 200, ok:true, 0 events, no error. Prefix made
+  optional in the split + detection regexes. Discovered while connecting the
+  owner's DNS3 Radicale (appt.sami) as a DashCaddy calendar source (owner
+  request: connect DNS3 calendar to DNS2 DashCaddy). 9-test ns suite
+  (extraction incl. mixed doc; empty multistatus; namespace-aware fixture
+  parse; undeclared element+attribute prefix rejection, both quote styles;
+  positive declared-attr case). Ops: NODE_EXTRA_CA_CERTS drop-in for the Sami
+  Home CA; source registered via authenticated API at the collection URL.
 - **DC-165 judge: grade B (round 5)** urn:ump:oqgczb6zv5bemekbxko7gi5rvfle6yoshwgfwsx4mbbj4xmg6paq
 - **DC-165: product/site uniformity + LLM-readable capabilities.** Site-vs-product
   audit reconciliation (owner: "advertise as Premium", "It should be LLM readable"):