AX Agent 권한·컨텍스트 카드 렌더 구조 분리 및 문서 갱신

권한 선택 팝업과 권한 상태 배너 렌더를 ChatWindow.PermissionPresentation partial로 분리했습니다.

컨텍스트 사용량 카드와 hover 팝업 렌더를 ChatWindow.ContextUsagePresentation partial로 분리해 메인 ChatWindow.xaml.cs의 책임을 줄였습니다.

README와 DEVELOPMENT 문서에 2026-04-06 07:31 (KST) 기준 변경 이력을 반영했고 Release 빌드 경고 0 오류 0을 확인했습니다.

docs/DEVELOPMENT.md

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 # AX Copilot - 媛쒕컻 臾몄꽌
 
+- Document update: 2026-04-06 07:31 (KST) - Split permission presentation logic out of `ChatWindow.xaml.cs` into `ChatWindow.PermissionPresentation.cs`. Permission popup row construction, popup refresh, section expansion persistence, and permission banner/status styling now live in a dedicated partial instead of the main window orchestration file.
+- Document update: 2026-04-06 07:31 (KST) - Split context usage card/popup rendering into `ChatWindow.ContextUsagePresentation.cs`. The Cowork/Code context usage ring, tooltip popup copy, hover close behavior, and screen-coordinate hit testing are now isolated from the rest of the chat window flow.
 - Document update: 2026-04-06 01:37 (KST) - Reworked AX Agent plan approval toward a more transcript-native flow. The inline decision card remains the primary approval path, while the `계획` affordance now opens the stored plan as a detail-only surface instead of acting like a required popup step.
 - Document update: 2026-04-06 01:37 (KST) - Expanded `OperationalStatusPresentationState` so runtime badge, compact strip, and quick-strip labels/colors/visibility are calculated together. `ChatWindow` now consumes a richer presentation model instead of branching on strip kinds and quick-strip counters independently.