Add initial Nebula Browser project skeleton: CMakeLists to configure and link CEF (including post-build steps to copy runtime and UI files), a Windows CEF-based entry (app/main.cpp) that initializes CEF and loads the bundled UI, and a full ui/ and assets/ tree (HTML, CSS, JS, fonts, icons, and branding images). Update .gitignore to ignore build/out, thirdparty/cef, IDE and common OS artifacts.
Portable mode now works on Windows, macOS, and Linux, storing user data in a 'user-data' folder within the app directory by default. The mode is enabled by default and can be disabled via NEBULA_PORTABLE=0. All file operations for history and search data now respect portable mode, using secure file writes where appropriate. Updated .gitignore and package.json to exclude portable data from versioning and packaging. Also fixed Bing icon filename case in home.html.
Introduces the Nebot plugin, providing a floating chat panel that communicates with a local or remote Ollama server and persists chat sessions. Adds dependencies for markdown rendering and code highlighting (dompurify, highlight.js, marked). Removes the sample-hello plugin. Updates site-history.json with recent browsing history.
Enhances the tab strip with ARIA roles, keyboard navigation, and improved drag-and-drop reordering. Refactors tab rendering for better accessibility, adds dedicated new-tab button, and updates styles for a more modern look and clearer tab controls.