framework: add event stream support

framework/framework/package.json

@@ -10,7 +10,7 @@
         "@hydrooj/utils": "workspace:^",
         "emoji-regex": "^10.4.0",
         "fs-extra": "^11.3.0",
-        "koa": "^2.15.3",
+        "koa": "^2.15.4",
         "koa-body": "^6.0.1",
         "koa-compress": "^5.1.1",
         "koa-router": "^13.0.1",