Complete CRUD operations for habits

Implement all missing endpoints for full habit management:
- GET /api/v1/habits - List all user habits
- GET /api/v1/habits/{id} - Get specific habit
- PUT /api/v1/habits/{id} - Update habit
- DELETE /api/v1/habits/{id} - Archive habit (soft delete)
- GET /api/v1/habits/{id}/entries - Get habit entry history
- DELETE /api/v1/habits/{id}/entries/{date} - Unmark habit (soft delete entry)

All endpoints include:
- TDD approach with comprehensive test coverage
- JWT authentication and ownership validation
- Proper error handling (404, 403, 400, 500)
- Clean architecture with separated commands/queries

internal/infrastructure/http/dto.go

@@ -13,6 +13,15 @@ type CreateHabitRequest struct {
 	TargetValue   *float64 `json:"target_value,omitempty"`
 }
 
+type UpdateHabitRequest struct {
+	Name          string   `json:"name"`
+	Description   string   `json:"description"`
+	SpecificDays  []int    `json:"specific_days,omitempty"`
+	SpecificDates []int    `json:"specific_dates,omitempty"`
+	CarryOver     bool     `json:"carry_over"`
+	TargetValue   *float64 `json:"target_value,omitempty"`
+}
+
 type HabitResponse struct {
 	ID            string     `json:"id"`
 	UserID        string     `json:"user_id"`
@@ -42,6 +51,24 @@ type TodaysHabitResponse struct {
 	IsCarriedOver bool      `json:"is_carried_over"`
 }
 
+type UserHabitResponse struct {
+	ID           string   `json:"id"`
+	Name         string   `json:"name"`
+	Type         string   `json:"type"`
+	Frequency    string   `json:"frequency"`
+	SpecificDays []int    `json:"specific_days,omitempty"`
+	TargetValue  *float64 `json:"target_value,omitempty"`
+	CarryOver    bool     `json:"carry_over"`
+}
+
+type HabitEntryResponse struct {
+	ID            string    `json:"id"`
+	HabitID       string    `json:"habit_id"`
+	ScheduledDate time.Time `json:"scheduled_date"`
+	CompletedAt   time.Time `json:"completed_at"`
+	Value         *float64  `json:"value,omitempty"`
+}
+
 type ErrorResponse struct {
 	Error string `json:"error"`
 }