add day-detail view to monthly history calendar

날짜 셀 클릭 시 그 날 예정된 습관별 완료/실패/미완료 상태를 htmx로 불러와 보여준다.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/services/log_service.py

@@ -6,7 +6,7 @@ from sqlalchemy.orm import Session
 
 from app.models.habit import Habit, HabitStatus, HabitType
 from app.models.habit_log import HabitLog, HabitLogStatus
-from app.schemas.habit_log import HabitStats, MonthlySummaryDay, TodayItem, WeeklyMatrixRow
+from app.schemas.habit_log import DayDetailItem, HabitStats, MonthlySummaryDay, TodayItem, WeeklyMatrixRow
 from app.schemas.level import LevelInfo
 from app.services import habit_service, level_service, push_service
 
@@ -182,6 +182,51 @@ def get_monthly_summary(db: Session, user_id: int, year: int, month: int) -> lis
     return summaries
 
 
+def get_day_detail(db: Session, user_id: int, target_date: date) -> list[DayDetailItem]:
+    """월별 캘린더에서 특정 날짜를 선택했을 때, 그 날 예정되어 있던 습관별 체크/실패/미결정 상태를 반환한다.
+
+    get_monthly_summary와 같은 규칙(현재 active 습관 기준, 습관 생성일 이전 제외, 과거 요일 변경
+    이력 미추적)을 그대로 따른다.
+    """
+    active_habits = habit_service.list_habits(db, user_id, status=HabitStatus.ACTIVE)
+    scheduled = [
+        h for h in active_habits if h.created_at.date() <= target_date and h.is_scheduled_on(target_date.weekday())
+    ]
+
+    habit_ids = [h.id for h in scheduled]
+    logs_by_habit: dict[int, HabitLogStatus] = {}
+    if habit_ids:
+        rows = db.execute(
+            select(HabitLog.habit_id, HabitLog.status).where(
+                HabitLog.habit_id.in_(habit_ids), HabitLog.log_date == target_date
+            )
+        ).all()
+        logs_by_habit = {r[0]: r[1] for r in rows}
+
+    today = date.today()
+    items = []
+    for h in scheduled:
+        log_status = logs_by_habit.get(h.id)
+        if log_status == HabitLogStatus.DONE:
+            status = "checked"
+        elif log_status == HabitLogStatus.FAILED:
+            status = "failed"
+        elif target_date < today:
+            status = "missed"
+        else:
+            status = "pending"
+        items.append(
+            DayDetailItem(
+                habit_id=h.id,
+                name=h.name,
+                habit_type=h.habit_type.value,
+                condition_text=h.condition_text,
+                status=status,
+            )
+        )
+    return items
+
+
 def summarize_completion_rate(summaries: list[MonthlySummaryDay], up_to: date) -> float:
     """월별 요약에서 up_to(보통 오늘)까지 지난 날짜만 모아 전체 완료율(%)을 계산한다.