Show HN: BraiNOTES, handwritten notes on your lecture PDFs in a browser tab

BraiNOTES is a browser-based application that allows users to take handwritten notes on PDFs in a browser tab, with features such as support for pen pressure, offline storage, and exportability to .brainotes files. The application is built using pdf.js and IndexedDB, and has a GitHub repository under the MIT license. It has two modes: Study mode, which allows users to read a PDF on one side of the tab and take notes on the other, and Board mode, which provides a whiteboard for tutoring or exercises. The application also has a snip tool for capturing formulae and diagrams, and a laser pointer tool for highlighting or drawing on the whiteboard. Future features include a video editor and animation tool, as well as integration with a MCP server for automated editing of videos and other tasks.