fix(tester): extend ListProblems endpoint

tester/v1/openapi.yaml

@@ -6,6 +6,19 @@ paths:
   /problems:
     get:
       operationId: ListProblems
+      parameters:
+        - name: page
+          in: query
+          required: true
+          schema:
+            type: integer
+            format: int32
+        - name: pageSize
+          in: query
+          required: true
+          schema:
+            type: integer
+            format: int32
       security:
         - bearerAuth: [ ]
       responses:
@@ -253,15 +266,50 @@ components:
         updated_at:
           type: string
           format: date-time
+    ProblemListItem:
+      type: object
+      required:
+        - id
+        - title
+        - memory_limit
+        - time_limit
+        - created_at
+        - updated_at
+      properties:
+        id:
+          type: integer
+          format: int32
+        title:
+          type: string
+        memory_limit:
+          type: integer
+          format: int32
+        time_limit:
+          type: integer
+          format: int32
+        created_at:
+          type: string
+          format: date-time
+        updated_at:
+          type: string
+          format: date-time
     ListProblemsResponse:
       type: object
       required:
         - problems
+        - page
+        - max_page
       properties:
         problems:
           type: array
           items:
-            $ref: '#/components/schemas/Problem'
+            $ref: '#/components/schemas/ProblemListItem'
+        page:
+          type: integer
+          format: int32
+        max_page:
+          type: integer
+          format: int32
     CreateProblemResponse:
       type: object
       required: