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/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")