Three pages carried names the 2026-07-28 specification does not use: "Multi-Round-Trip Results" for
the pattern the specification titles Multi Round-Trip Requests (MRTR) and serves at basic/patterns/mrtr -
the results are the `InputRequiredResult` wire type, not the feature - plus "Completions" for the utility
the specification titles Completion, and "Notification Subscriptions" for the pattern it titles Subscriptions.
Retitle the three pages to the specification's names, move them to /server/mrtr/ and /client/mrtr/,
/server/completion/, and /server/subscriptions/ following the specification's slugs, update every internal reference,
and keep the URLs published with v1.3.0 working via jekyll-redirect-from.
The Discovery page keeps its title but moves from /server/discovery/ to /server/discover/, matching
the specification's slug and the `server/discover` RPC, with its published URL redirected the same way.