fix: SKILL.md frontmatter에 endpoints 섹션 추가 (executor HTTP 메서드 SSOT)

- skill-calendar: create_event(POST), list_events(GET), delete_event(DELETE)
- skill-email: send(POST), read(GET), process(POST)

연결: rb8001 PR #188

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

skills/skill-calendar/SKILL.md

@@ -4,6 +4,10 @@ description: 캘린더 일정 생성, 조회, 삭제. 사용자가 "내일 2시
 runtime:
   kind: external_http
   service_url_env: SKILL_CALENDAR_URL
+  endpoints:
+    create_event: { method: POST, path: /api/events }
+    list_events: { method: GET, path: /api/events }
+    delete_event: { method: DELETE, path: "/api/events/{event_id}" }
 ---
 
 # skill-calendar

skills/skill-email/SKILL.md

@@ -4,6 +4,10 @@ description: Gmail API를 통한 이메일 읽기·쓰기·요약. 사용자가
 runtime:
   kind: external_http
   service_url_env: SKILL_EMAIL_URL
+  endpoints:
+    send: { method: POST, path: /send }
+    read: { method: GET, path: /messages }
+    process: { method: POST, path: /process }
 ---
 
 # skill-email