- Добавил аутентификацию с помощью Spring Security.

- Реализовал кастомные  CustomUserDetails и CustomUserDetailsService

https://www.youtube.com/watch?v=WDlifgLS8iQ&list=PLU2ftbIeotGoGSEUf54LQH-DgiQPF2XRO&index=3
https://spring.io/guides/gs/securing-web
https://medium.com/@CodeWithTech/spring-security-with-jdbcuserdetailsmanager-and-custom-userdetailsservice-a-complete-guide-248ddce0196c

pom.xml

@@ -56,6 +56,15 @@
             <artifactId>mysql-connector-j</artifactId>
             <scope>runtime</scope>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-security</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.security</groupId>
+            <artifactId>spring-security-core</artifactId>
+            <version>6.3.1</version>
+        </dependency>
     </dependencies>
 
     <build>