Added TypeScript for frontend

Added type definitions for components, functions, data
Added guards for network responses
fixes #8

front/src/assets/category.ts

@@ -0,0 +1,41 @@
+import { isLiteralUnion } from "../utils/types"
+
+const categories = ["PORRIDGE", "conspects", "milk", "bred", "wathing", "cloth",
+"fruits_vegatables", "soup", "dinner", "conserves", "pens", "other_things"] as const
+type Category = typeof categories[number]
+
+const isCategory = (obj: unknown): obj is Category => isLiteralUnion(obj, categories) 
+
+const categoryGraphics = new Map<Category, string>([
+    ["PORRIDGE", "static/PORRIDGE.jpg"],
+    ["conspects", "static/conspects.jpg"],
+    ["milk", "static/milk.jpg"],
+    ["bred", "static/bred.jpg"],
+    ["wathing", "static/wathing.jpg"],
+    ["cloth", "static/cloth.jpg"],
+    ["fruits_vegatables", "static/fruits_vegatables.jpg"],
+    ["soup", "static/soup.jpg"],
+    ["dinner", "static/dinner.jpg"],
+    ["conserves", "static/conserves.jpg"],
+    ["pens", "static/pens.jpg"],
+    ["other_things", "static/other_things.jpg"]
+
+])
+
+const categoryNames = new Map<Category, string>([
+    ["PORRIDGE", "PORRIDGE"],
+    ["conspects", "Конспекты"],
+    ["milk", "Молочные продукты"],
+    ["bred", "Хлебобулочные изделия"],
+    ["wathing", "Моющие средства"],
+    ["cloth", "Одежда"],
+    ["fruits_vegatables", "Фрукты и овощи"],
+    ["soup", "Супы"],
+    ["dinner", "Ужин"],
+    ["conserves", "Консервы"],
+    ["pens", "Канцелярия"],
+    ["other_things", "Всякая всячина"]
+])
+
+export type { Category }
+export { categoryNames, categoryGraphics, isCategory }