chore(backend): update package-lock and upgrade eslint with config to new default config format

backend/.eslintrc.json

@@ -1,6 +0,0 @@
-{
-  "extends": ["eslint:recommended", "plugin:@typescript-eslint/recommended"],
-  "parser": "@typescript-eslint/parser",
-  "plugins": ["@typescript-eslint"],
-  "root": true
-}

backend/eslint.config.mjs

@@ -0,0 +1,27 @@
+import { defineConfig } from "eslint/config";
+import typescriptEslint from "@typescript-eslint/eslint-plugin";
+import tsParser from "@typescript-eslint/parser";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import js from "@eslint/js";
+import { FlatCompat } from "@eslint/eslintrc";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const compat = new FlatCompat({
+    baseDirectory: __dirname,
+    recommendedConfig: js.configs.recommended,
+    allConfig: js.configs.all
+});
+
+export default defineConfig([{
+    extends: compat.extends("eslint:recommended", "plugin:@typescript-eslint/recommended"),
+
+    plugins: {
+        "@typescript-eslint": typescriptEslint,
+    },
+
+    languageOptions: {
+        parser: tsParser,
+    },
+}]);

backend/package.json

@@ -74,9 +74,10 @@
     "@typescript-eslint/eslint-plugin": "^8.6.0",
     "@typescript-eslint/parser": "^8.6.0",
     "cross-env": "^7.0.3",
-    "eslint": "^9.10.0",
+    "eslint": "9.23.0",
-    "eslint-config-prettier": "^9.1.0",
+    "eslint-config-next": "^15.2.4",
-    "eslint-plugin-prettier": "^5.2.1",
+    "eslint-config-prettier": "^10.1.1",
+    "eslint-plugin-react": "^7.37.4",
     "newman": "^6.2.1",
     "prettier": "^3.3.3",
     "prisma": "^6.4.1",