Window integration: display rendered HTML page #37

Phase 3, Issue 7: Window Integration#

Connect all Phase 3 components to display a rendered HTML page in the AppKit window.

Requirements#

Update the browser crate (crates/browser) to:

1. Load HTML — read an HTML string (hardcoded or from a file path argument)
2. Parse — tokenize and tree-build into a DOM
3. Layout — run block layout with a system font
4. Render — paint into a CG bitmap
5. Display — show the bitmap in the AppKit window via the existing WeView

Browser main loop:

• Load a system font via FontRegistry or load_system_font()
• Parse the HTML into a DOM
• Run layout with viewport dimensions from the window
• Render to bitmap
• Display in the window
• Handle window resize (re-layout and re-render)

Command-line:

• cargo run -p we-browser — show a default "Hello World" page
• cargo run -p we-browser -- file.html — load and render a local HTML file

Acceptance criteria#

• cargo run -p we-browser opens a window showing rendered HTML with visible text
• Text is anti-aliased and readable
• Block elements are visually stacked
• Headings appear larger than body text
• Window resize triggers re-layout and re-render
• Can load an HTML file from command line argument
• cargo clippy --workspace -- -D warnings passes
• cargo test --workspace passes
• No new unsafe code outside of platform crate