Adding AirplaneType model

core/src/main/java/cz/muni/fi/pa165/core/data/domain/AirplaneType.java

+package cz.muni.fi.pa165.core.data.domain;
+
+import jakarta.persistence.*;
+
+import java.io.Serializable;
+import java.util.Objects;
+
+@Entity(name = "airplane_type")
+public class AirplaneType implements Serializable {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false, unique = true)
+    private String name;
+
+    public AirplaneType() {
+    }
+
+    public AirplaneType(String name) {
+        this.name = name;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof AirplaneType airplaneType)) {
+            return false;
+        }
+        return Objects.equals(getName(), airplaneType.getName());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getName());
+    }
+}