feat(backend): Question + Answer entities toegevoegd; kleine verbeteringen.

backend/src/entities/questions/answer.entity.ts

@@ -0,0 +1,19 @@
+import {Entity, ManyToOne, PrimaryKey, Property} from "@mikro-orm/core";
+import {Question} from "./question.entity";
+import {Teacher} from "../users/teacher.entity";
+
+@Entity()
+export class Answer {
+
+    @ManyToOne({entity: () => Teacher, primary: true})
+    author!: Teacher;
+
+    @ManyToOne({entity: () => Question, primary: true})
+    toQuestion!: Question;
+
+    @PrimaryKey({type: "datetime"})
+    timestamp: Date;
+
+    @Property({type: "text"})
+    content: string;
+}