Appetite tends to drop a bit at 12 months so it would work out that's the amount of time you've been seeing less of an interest in food. It'll pick up again when she needs it to. Also toddler portions are really small, likely much smaller than most of us think at first, if you kept a strict food diary for a week or so you might be surprised to find she is balancing out her needs across that time even though each meal appears to be very little.
You could also look at how much milk she's having, at this age solids need to take preference over milk and if she is getting more milk than she needs she'll be too full for solids.
Although you say she is light if that's her natural weight and she gains weight and has energy etc there is nothing wrong with it. My boy is quite petite too, it's normal for him. I also remember being concerned around this age about his eating, but it's picked up again and now he really enjoys his meals unless he is poorly (but he is still petite that's just his build).
I probably wouldn't go to such lengths to distract her into eating, it's setting up some habits that you are unlikely to be happy with further down the line and she is unlikely to starve herself, the survival instinct will keep her eating what she needs. Maybe try to relax a bit and enjoy your own meal instead of focusing on her, seeing other people enjoy their food is a great motivator to humans, we are social eaters. I know it's easier said than done, we all worry about our LOs hey? x
