AX Agent 대화 목록 렌더를 별도 프레젠테이션 파일로 분리하고 문서 이력을 갱신한다

좌측 대화 목록의 메타 필터링, spotlight 계산, 그룹 렌더, 더 보기 페이지네이션, 목록 카드 조립을 ChatWindow.ConversationListPresentation.cs로 이동해 ChatWindow.xaml.cs가 transcript/runtime orchestration에 더 집중하도록 정리했다.

README와 DEVELOPMENT 문서에 2026-04-06 10:18 (KST) 기준 변경 이력을 반영했고, dotnet build 검증 결과 경고 0 / 오류 0을 확인했다.

docs/DEVELOPMENT.md

@@ -4921,3 +4921,5 @@ ow + toggle ?쒓컖 ?몄뼱濡??ㅼ떆 ?뺣젹?덈떎.
 - Document update: 2026-04-06 09:58 (KST) - Rewrote `docs/AX_AGENT_REGRESSION_PROMPTS.md` into a repeatable regression ritual with explicit failure classes (`blank-reply`, `duplicate-banner`, `bad-approval-flow`, `queue-drift`, `restore-drift`, `status-noise`) and required prompt bundles per change area so runtime/transcript work can be validated consistently.
 - Document update: 2026-04-06 10:07 (KST) - Split topic preset rendering and selection flow out of `ChatWindow.xaml.cs` into `ChatWindow.TopicPresetPresentation.cs`. Preset card creation, custom preset dialogs/context menus, and `SelectTopic(...)` metadata application now live in a dedicated partial.
 - Document update: 2026-04-06 10:07 (KST) - This keeps the main chat window more orchestration-focused and narrows the remaining maintainability work to small follow-up polish rather than any large structural split.
+- Document update: 2026-04-06 10:18 (KST) - Split conversation list rendering out of `ChatWindow.xaml.cs` into `ChatWindow.ConversationListPresentation.cs`. Conversation meta filtering, spotlight calculation, grouped list rendering, load-more pagination, and sidebar conversation-row assembly now live in a dedicated partial.
+- Document update: 2026-04-06 10:18 (KST) - This keeps the main chat window more focused on transcript/runtime orchestration while isolating sidebar list presentation for future UX tuning and parity work.