p0lloc/perfice ? reverse-engineered prompt

Build me a self tracking app where I can log different parts of my life like sleep, mood, food, habits, or anything else I want to follow.

I want it to feel simple and private first, with data saved on the device by default, and a clean way to see patterns over time. It should let me create custom trackables, set goals, enter daily values, and see charts or insights that help me understand how one thing affects another, like whether better sleep improves mood.

Please also add export and import so I can move my data around easily, ideally with CSV and JSON. If there is a backend for accounts or syncing, make it optional and easy to connect later, but the app should still work well without it. Make the design modern and friendly, and if it makes sense, include a mobile friendly version too. Look up current docs online if you need to.