Lets look at your concerns:
1) Record: Assuming that she is charged as a juvenile, that record will be sealed. As such, once she becomes 18, this incident should have little chance of causing future problems. In the event that she decides to do this again, as an adult, the existence of the juvenile record could be considered. As you can see, it is imperative that she learn from this.
2) Job: The juvenile record won't affect her job prospects. As a juvenile, it won't be visible, so any negotiations or concerns about its immediate impact are minimal. The real concern her is employer recommendations.... and her admission has already been noted... and impact made. There is nothing that can be done about that... except to accept that it will likely impact any immediate job prospects.
3) Liability: The criminal aspect (#1 above) is only one concern. The other will be that, depending on the merchant, in the next few weeks or so, you will probably get a demand letter for 'civil damages' from the merchant. Texas statutes (and most other states) allow the merchant to not only recover the value of the property taken, but also to recover their 'reasonable costs' that they incur in maintaining store security (personnel, cameras, anti-theft tags, etc.).
4) Lesson learned: Sounds to me like she is the responsible party here. Apparently, she recognizes that she was wrong and is willing to be responsible for her actions. With 'todays kids', that is something to commend her for. She is showing that she understand right from wrong, she did an incorrect thing and is willing to accept the consequences of her actions. That is a rare commodity in todays "I am a victim" mentality. Be sure to praise her maturity while noting disappointment for her actions.