Updated README

README.md

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+# JHS (J HTTP Server) IDE
+
+JHS is a modern, web-based development environment for the J programming language. It provides a full-featured IDE experience directly in the browser, allowing for interactive execution, script editing, and advanced data visualization.
+
+The ide/jhs addon is the JHS IDE for j701 and later releases.
+
+## Key Features
+
+- **Interactive Terminal (`jijx`)**: A specialized REPL interface with command history recall, multi-line paste handling, and real-time output updates via AJAX.
+- **CodeMirror 6 Editor**: A high-performance code editor with custom J syntax highlighting, themes (Selenized Light/Dark), bracket matching, and multiple selection support.
+- **Graphics & Visualization**: 
+    - Integrated **D3.js** and **Chart.js** for high-quality plotting.
+    - Custom HTML5 Canvas support via `jhjcanvas.js`.
+    - **WebGL** support via `glMatrix`.
+- **Data Management**: Integration with **Handsontable** for viewing and editing J arrays in a spreadsheet-like interface.
+- **Single Page App (SPA) Support**: Capability to run multiple IDE components (terminal, files, locales) within a single tab using an internal iframe-based window manager.
+- **Responsive Design**: Support for mobile browsers with specialized editors and touch-friendly interaction handles.
+
+## Project Structure
+
+- `/js/jsoftware/`: Core JHS logic.
+    - `jscore.js`: The framework's engine. Handles AJAX (`jdoajax`), event routing (`jevdo`), and UI command processing (`jhrcmds`).
+    - `jijx.js`: Implements the interactive terminal window.
+    - `editor.js`: Integration of CodeMirror 6 for J script editing.
+- `/widget/`: UI widgets.
+    - `jhjcanvas.js`: Bridge between J sentences and HTML5 Canvas drawing commands.
+- `/js/3rdparty/`: Bundled distributions of D3, Chart.js, Handsontable, and other utilities.
+
+## Framework Architecture
+
+The frontend uses a custom event system where UI interactions (clicks, keypresses) are routed through `jscore.js`. 
+
+1. **Event Handling**: `jev(event)` captures UI events and translates them into J sentences.
+2. **AJAX Protocol**: `jdoajax` sends POST requests to the J backend. Data is often delimited by `JASEP` (`\x01`).
+3. **Server Commands**: The backend can return specialized commands via JSON (handled by `jhrcmds`) to dynamically modify the DOM, open pages, or update styles.
+
+## Keyboard Shortcuts
+
+The IDE uses an "Esc-lead" shortcut system:
+- **Esc then Q**: Close all pages and exit the server.
+- **Esc then 2**: Scroll terminal to the bottom.
+- **Ctrl+Enter**: Execute the current input line.
+- **Ctrl+S** (in editor): Save script.
+- **Ctrl+R** (in editor): Run script.
+
+## Technical Stack
+
+- **Core**: Vanilla JavaScript
+- **Editor**: CodeMirror 6 / Lezer (for parsing J)
+- **Visuals**: D3.js v4, Chart.js v4
+- **Grid**: Handsontable
+- **Styles**: `style-mod` for dynamic CSS generation
+
+---
+*Part of the Jsoftware IDE suite.*