It's not recommended to compost cat excrement or to grow edibles in a 'litterbox' garden--
However, the question "is it safe to consume anything grown from that soil?" and the answer "no, it is not" might cause freak out.
Don't freak out!
It could have been 'safe' enough...even if not desirable or without risk...
Basic hygiene principles are advised i.e. wash your edible plants and wash your hands before you put them in your mouth; don't eat feces and don't eat fecal soil, or the soil where varmints have died and recently decomposed
And regarding Toxo specifically,
Plants don't absorb Toxo oocysts and transmit the parasite to people. (Bacteria, on the other hand can sometimes be taken up by plants. Remember the deadly E. coli O157 spinach? Anyway, that's not a cat thing but is a legit concern with improperly composted cattle manure.)
Back to Toxo, not every cat has it nor do they shed it continuously. They get the infection when they eat infected meat (most likely rodents/birds/what have you if they are killing and eating infected critters in the neighborhood, or they can even get it if they are fed raw or under-cooked infected meat from the store).
They only shed the oocysts in their feces for a couple weeks after that initial infection--not their whole lives. They do shed a lot of them in a short time period and the oocysts can remain viable and pathogenic in the soil for up to a year or so. These then infect the rodents/birds/what have you--anything that eats them intentionally or accidentally.
Most likely cats to be sharing the parasite are the feral or indoor-outdoor young cat/kitten types rather than older cats.
It's entirely possible that your neighbors' cat didn't even put any Toxo in there
Still, though, good idea to employ some cat proofing strategies for your compost, because you just never know who might think it looks like a good place to go