Add refresh token endpoint

src/main/java/com/faf223/expensetrackerfaf/controller/auth/AuthenticationController.java

@@ -23,4 +23,9 @@ public class AuthenticationController {
     public ResponseEntity<AuthenticationResponse> authenticate(@RequestBody AuthenticationRequest request) {
         return ResponseEntity.ok(service.authenticate(request));
     }
+
+    @PostMapping("/refresh")
+    public ResponseEntity<AuthenticationResponse> refreshAccessToken(@RequestBody TokenRefreshRequest refreshRequest) {
+        return ResponseEntity.ok(service.refreshAccessToken(refreshRequest));
+    }
 }

src/main/java/com/faf223/expensetrackerfaf/controller/auth/AuthenticationResponse.java

@@ -1,5 +1,6 @@
 package com.faf223.expensetrackerfaf.controller.auth;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
 import lombok.Data;
@@ -11,5 +12,8 @@ import lombok.NoArgsConstructor;
 @NoArgsConstructor
 public class AuthenticationResponse {
 
-    private String token;
+    @JsonProperty("access_token")
+    private String accessToken;
+    @JsonProperty("refresh_token")
+    private String refreshToken;
 }

src/main/java/com/faf223/expensetrackerfaf/controller/auth/TokenRefreshRequest.java

@@ -0,0 +1,8 @@
+package com.faf223.expensetrackerfaf.controller.auth;
+
+import lombok.Data;
+
+@Data
+public class TokenRefreshRequest {
+    private String refreshToken;
+}