fix review findings: stale service prose + catalog cleanup

Codex review of the PR1 diff surfaced docs/cleanup drift:
- LlmService class JSDoc still advertised "streaming / non-streaming call
  surfaces, both interceptable via waterfall events" — corrected to the single
  streaming surface; regenerated the cordis catalog so its mirror updates.
- Removed GenerateResult from gen-cordis-catalog.ts LINK_MAP (the type is gone).
- The adapter-change RFC's acceptance criterion named the retired
  verify-event-taxonomy gate; updated to verify-cordis-catalog.
- Dropped the now-tautological "streaming and one-shot assembly agree" property
  test (the streaming/one-shot distinction lived in the removed flush API;
  usage/finish remain covered by assembler.spec.ts and the finish property).

scripts/gen-cordis-catalog.ts

@@ -64,7 +64,6 @@ const LINK_MAP: Record<string, string> = {
   Message: 'core.md',
   MessageSource: 'core.md',
   GenerateOptions: 'core.md',
-  GenerateResult: 'core.md',
   SessionEvent: 'core.md',
   StreamChunk: 'llm-streaming.md',
   TurnEndReason: 'session.md',