Add eslint-plugin-relay rules (warning only)

Signed-off-by: Émile Ré <emile@getprobo.com>

packages/eslint-config/package.json

@@ -14,6 +14,7 @@
     "#baseConfigs": "./src/baseConfigs.ts",
     "#tsConfigs": "./src/tsConfigs.ts",
     "#reactConfigs": "./src/reactConfigs.ts",
+    "#relayConfigs": "./src/relayConfigs.ts",
     "#importsConfigs": "./src/importsConfigs.ts",
     "#languageOptionsConfigs": "./src/languageOptionsConfigs.ts",
     "#stylisticConfigs": "./src/stylisticConfigs.ts"
@@ -30,10 +31,12 @@
     "eslint-plugin-import-x": "^4.16.1",
     "eslint-plugin-react": "^7.37.5",
     "eslint-plugin-react-hooks": "^7.0.1",
+    "eslint-plugin-relay": "^2.0.0",
     "globals": "^17.0.0",
     "typescript-eslint": "^8.53.1"
   },
   "devDependencies": {
+    "@types/eslint-plugin-relay": "^1.0.0",
     "eslint": "^9.39.2",
     "typescript": "^5.8.3"
   }