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.
Introduces a plugin architecture, including a PluginManager, plugin loading in main and renderer processes, and a sample plugin demonstrating menu, IPC, and context menu contributions. Adds a Plugins tab to the settings UI for managing plugins (enable/disable, reload), and updates preload.js to load renderer preloads from plugins. Documentation for plugin development is included in README-PLUGINS.md.
andrew