Hello, and welcome. I am a licensed attorney and happy to assist.
I'm sorry to hear of the situation, and understand the privacy concerns. Ordinarily, cameras filming activity in a public area do not violate privacy from a legal perspective, but you may find some relief in the association governing documents. The first thing to do will be to take a look at those and see if the type of behavior undertaken is prohibited. If so, you can bring the information to the Board and the filming should stop. Also, maybe take a snapshot of the cameras and blow them up to ascertain whether there are any "illegal" characteristics, such as those that might enable the neighbor to be seen at night in a manner of clarity that would not enable her to be seen at night by the naked eye at the same distance. Such equipment, if used, is definitely a violation of privacy and the neighbor being filmed could sue for damages. Likewise, if the cameras are strong enough to see inside the windows, when normal sight from the same distance does not, the filming is an actionable invasion of privacy. Also, check the governing documents for rules about feeding cats. If there are none, the filming is harassing and may interfere with the use and enjoyment of the neighbor's property, such that the neighbor would have grounds for a lawsuit in nuisance. Another potentially helpful option is neighborhood pressure against the boardmembers who approved this practice. After all, if it can happen to one neighbor, it can happen to others and nobody wants to be filmed going about their business in the community for purposes of assessing fines.
I hope this information helps. If you need additional information or clarification, just let me know. I'm here to help. If I have addressed your question, please remember to leave positive feedback when prompted.