SunTzv/pdfilter ? reverse-engineered prompt

Build me a client side web app for filtering PDF files in the browser.

I want to upload a PDF, preview it right away, and tweak the look with simple controls like brightness, contrast, saturation, hue, blur, and opacity. Please include a few one click presets too, like invert, grayscale, sepia, warm, and cool, so it’s easy to get different styles fast.

The preview should update in real time as I move the controls, and then I should be able to export the edited PDF when I’m happy with it. Keep the experience smooth and simple, and make sure the pages keep their quality and proportions when exported. Since everything should run locally in the browser, do not send the file to any server.

Use the existing app structure if it helps, and look up current docs online if you need to.