Flutter App Bug Fixing

I have a production-ready Flutter codebase that is misbehaving on Android. The problems show up every time I run the app—no randomness involved—so you’ll be able to reproduce them quickly. What I’m seeing: • UI/UX issues: the user screen doesn't display • Performance problems: janky scrolls and noticeable frame drops on list-heavy pages. • Functionality errors: many API-driven features fail to return data even though the backend is healthy. Your task is to dive into the existing Dart code, locate the root causes and deliver clean, well-commented fixes. Once done, I expect a debug build for review, followed by a signed release APK/AAB. All changes should compile without warnings, run smoothly on Android 8+ devices, and keep the current architecture intact. I work with Git so please push each logical fix to its own commit; that will make testing easier on my side. If a third-party package upgrade is required, let me know first—I prefer minimal dependency changes. Let me know your estimated turnaround and any clarifying questions.