Remove unnecessary comments from codebase

Clean up obvious and redundant comments that don't add value:
- Remove step-by-step comments in command handlers
- Remove obvious test setup comments
- Keep only meaningful comments that explain why, not what

internal/application/commands/archive_habit.go

@@ -23,20 +23,16 @@ func NewArchiveHabitHandler(habitRepo repositories.HabitRepository) *ArchiveHabi
 }
 
 func (h *ArchiveHabitHandler) Handle(ctx context.Context, cmd ArchiveHabitCommand) error {
-	// Find existing habit
 	habit, err := h.habitRepo.FindByID(ctx, cmd.HabitID)
 	if err != nil {
 		return err
 	}
 
-	// Check ownership
 	if habit.UserID != cmd.UserID {
 		return errors.ErrUnauthorized
 	}
 
-	// Archive the habit (idempotent operation)
 	habit.Archive()
 
-	// Save changes
 	return h.habitRepo.Update(ctx, habit)
 }

internal/application/commands/archive_habit_test.go

@@ -98,7 +98,6 @@ func TestArchiveHabitHandler_CanArchiveAlreadyArchivedHabit(t *testing.T) {
 
 	err := handler.Handle(context.Background(), cmd)
 
-	// Should be idempotent - no error
 	if err != nil {
 		t.Fatalf("Expected no error for already archived habit, got %v", err)
 	}

internal/application/commands/unmark_habit.go

@@ -30,7 +30,6 @@ func NewUnmarkHabitHandler(
 }
 
 func (h *UnmarkHabitHandler) Handle(ctx context.Context, cmd UnmarkHabitCommand) error {
-	// Verify habit exists and user owns it
 	habit, err := h.habitRepo.FindByID(ctx, cmd.HabitID)
 	if err != nil {
 		return err
@@ -40,8 +39,6 @@ func (h *UnmarkHabitHandler) Handle(ctx context.Context, cmd UnmarkHabitCommand)
 		return errors.ErrUnauthorized
 	}
 
-	// Find the entry for the scheduled date
-	// We search within the same day
 	startOfDay := time.Date(
 		cmd.ScheduledDate.Year(),
 		cmd.ScheduledDate.Month(),
@@ -56,7 +53,6 @@ func (h *UnmarkHabitHandler) Handle(ctx context.Context, cmd UnmarkHabitCommand)
 		return err
 	}
 
-	// Find the entry for this date
 	var targetEntryID string
 	for _, entry := range entries {
 		if entry.ScheduledDate.Equal(cmd.ScheduledDate) {
@@ -69,6 +65,5 @@ func (h *UnmarkHabitHandler) Handle(ctx context.Context, cmd UnmarkHabitCommand)
 		return errors.ErrNotFound
 	}
 
-	// Hard delete the entry
 	return h.entryRepo.Delete(ctx, targetEntryID)
 }

internal/application/commands/unmark_habit_test.go

@@ -119,7 +119,6 @@ func TestUnmarkHabitHandler_ReturnsErrorWhenEntryNotFound(t *testing.T) {
 		habitToReturn: habit,
 	}
 
-	// No entries
 	entryRepo := &mockEntryRepoForUnmark{
 		entries: []*entities.HabitEntry{},
 	}

internal/application/commands/update_habit.go

@@ -30,28 +30,23 @@ func NewUpdateHabitHandler(habitRepo repositories.HabitRepository) *UpdateHabitH
 }
 
 func (h *UpdateHabitHandler) Handle(ctx context.Context, cmd UpdateHabitCommand) error {
-	// Validate input
 	if strings.TrimSpace(cmd.Name) == "" {
 		return errors.ErrInvalidInput
 	}
 
-	// Find existing habit
 	habit, err := h.habitRepo.FindByID(ctx, cmd.HabitID)
 	if err != nil {
 		return err
 	}
 
-	// Check ownership
 	if habit.UserID != cmd.UserID {
 		return errors.ErrUnauthorized
 	}
 
-	// Cannot update archived habits
 	if !habit.IsActive() {
 		return errors.ErrInvalidInput
 	}
 
-	// Update fields
 	habit.Name = cmd.Name
 	habit.Description = cmd.Description
 	habit.CarryOver = cmd.CarryOver
@@ -59,6 +54,5 @@ func (h *UpdateHabitHandler) Handle(ctx context.Context, cmd UpdateHabitCommand)
 	habit.SpecificDays = cmd.SpecificDays
 	habit.SpecificDates = cmd.SpecificDates
 
-	// Save changes
 	return h.habitRepo.Update(ctx, habit)
 }

internal/domain/entities/user_test.go

@@ -32,7 +32,6 @@ func TestNewUser(t *testing.T) {
 		t.Error("UpdatedAt should not be zero")
 	}
 
-	// CreatedAt and UpdatedAt should be very close in time
 	diff := user.UpdatedAt.Sub(user.CreatedAt)
 	if diff < 0 || diff > time.Second {
 		t.Errorf("CreatedAt and UpdatedAt should be nearly identical, diff: %v", diff)

internal/shared/utils/date_utils_test.go

@@ -6,7 +6,6 @@ import (
 )
 
 func TestShouldAppearToday_Daily(t *testing.T) {
-	// Daily habits should always appear
 	result := ShouldAppearToday("DAILY", nil, nil, time.Now())
 	if !result {
 		t.Error("Daily habit should appear every day")