test(sdk): snapshot suite over the SDK path; docs for the SDK stack

- examples/jsonrpc-agent gains its first snapshot suite (sdk.snapshot.ts):
  the real dsh-jsonrpc-agent runtime driven through the real dsh-sdk-client,
  keyless llm-replay behind a new cordis.snapshot.yml overlay; three recorded
  scenarios (text turn, bash tool, spawn subagent) pin the notification
  stream, the SDK turn result, and the persisted parent+child session logs.
- Bilingual READMEs for dsh-sdk-protocol / dsh-sdk-client / dsh-subagent-sdk;
  sdk/ and subagent/ group tables extended; dsh-jsonrpc README points at the
  extracted protocol package; Agent Note (en+zh) owns the decision.
- The proposed make-jsonrpc-directional note is updated for the transport's
  new home and its second (client) consumer.
- Model Experience sentence allowlist entries for the two client-side
  packages; module graph + config catalog regenerated; i18n pairings
  recorded. doc-sync passes 24/24.

packages/ui/jsonrpc/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write
-README.md: 9297147b7a53739c46871b527ce51868eac1e244
-README.zh.md: 62596197b95729215408dfc1496c129ace6cbad4
+README.md: 96dae46c9c6ecce6643bb408a5e57c2db2275a83
+README.zh.md: 2c257b13a15ad3c6c1bf0c4dd44a04e308e8f0b0