Are all vegetables edible?
Since this is an app for general users, not an app for biologists, any layperson perceives all vegetables as edible. That is supported by the first two dictionary definitions of "vegetable," meaning the two definitions most commonly used, which are:
- any plant whose fruit, seeds, roots, tubers, bulbs, stems, leaves,
or flower parts are used as food, as the tomato, bean, beet, potato,
onion, asparagus, spinach, or cauliflower.
- the edible part of such a plant, as the tuber of the potato.
Above, you'll note in bold the parts of the definitions that explicitly define "vegetable" as being food, as being edible. Also, note that these are layperson definitions, how people in general use and perceive the term, people like app users, not scientific definitions. Were they scientific definitions, the first definition wouldn't include as an examples "tomato" and "bean," which are scientifically classified as fruit since they grow on a vine and contain seeds. That's why the definition itself uses "fruit" and "or," meaning not all plants "fruit" are considered vegetables in this lay definition, but just some, like tomatoes and beans, whereas other fruits, like bananas and grapes, aren't considered vegetables by laypeople.
Are herbs considered as vegetables?
Again, there is a difference between what laypeople would say and what scientists would say. A scientist would say an "herb" is a vegetable because any plant that's edible, like an "herb" is, is a vegetable. However, laypeople don't consider an "herb" to be a "vegetable" but its own thing, an "herb," their own thing, a plant that may be eaten but whose primary use isn't sustenance but instead is "valued for its medicinal properties, flavor, scent, or the like."
Are culinary goods edible?
No. "Culinary goods" are cooking utensils.
Is there one universal word for edible plant-based diet (veggies, fruits, flowers, herbs, ...)?
Yes, it's "vegetarian diet" or "vegetarianism." While many may focus on the fact that vegetarians don't eat meat, especially nonvegetarians, as that is its greatest contrast to a "regular" diet, the word itself was coined to put focus on what they do eat, which is vegetables, not what they don't eat.