ie-js: implement DOM properties as getters/setters and window global

[thomasnemer]

Goal

Real websites expect DOM properties (textContent, innerHTML, className, style) as getter/setter properties, not methods. Also need the window global object.

Current state

• textContent exposed as getTextContent()/setTextContent() methods
• No innerHTML
• No window object (location, navigator, document is on global directly)
• No className/classList as properties
• No element.style property access

Implementation needed

• Use boa's PropertyDescriptor with accessor functions for element properties
• textContent, innerHTML, className, id as getter/setter properties
• element.style.color etc. (CSSStyleDeclaration)
• window global: window.location, window.navigator, window.document
• window.onload / DOMContentLoaded event firing after parse

Impact

Most real-world JS will fail without these. This is the #1 JS compatibility gap.