feat: Add WebView node for embedding web content in worlds

docs/scripting/nodes/types/WebView.md

@@ -0,0 +1,143 @@
+# WebView
+
+Displays web content as an iframe that can exist in either world space (positioned in 3D) or screen space (HUD/overlay).
+
+```jsx
+// World-space webview
+const tvScreen = app.create('webview', {
+  src: 'https://www.youtube.com/embed/dQw4w9WgXcQ',
+  width: 1920,
+  height: 1080,
+  space: 'world',
+  size: 0.002, // Scale factor for world space
+})
+tvScreen.position.set(0, 3, -8)
+app.add(tvScreen)
+
+// Screen-space webview (HUD)
+const hudInfo = app.create('webview', {
+  src: 'https://example.com/info',
+  width: 300,
+  height: 200,
+  space: 'screen'
+})
+hudInfo.position.set(0.9, 0.1, 0) // Top-right corner
+app.add(hudInfo)
+```
+
+## Spaces
+
+### World Space (`space: 'world'`)
+- WebView is positioned in 3D world coordinates
+- Scales with distance from camera
+- Follows parent transforms
+- Good for: TVs, monitors, information panels in the world
+
+### Screen Space (`space: 'screen'`)
+- WebView is fixed to the screen/camera
+- Position uses viewport coordinates (0-1)
+- Always renders on top
+- Good for: HUD elements, overlays, UI panels
+
+## Properties
+
+### `.src`: String
+
+The URL of the web content to display.
+Defaults to `null`.
+
+### `.width`: Number
+
+The width of the webview in pixels.
+Defaults to `640`.
+
+### `.height`: Number
+
+The height of the webview in pixels.
+Defaults to `480`.
+
+### `.space`: String
+
+The rendering space for the webview. Options are `'world'` or `'screen'`.
+Defaults to `'world'`.
+
+### `.size`: Number
+
+Scale factor for world-space webviews (pixels to meters conversion).
+Only applies when `space: 'world'`.
+Defaults to `0.01`.
+
+### `.visible`: Boolean
+
+Whether the webview is visible.
+Defaults to `true`.
+
+### `.opacity`: Number
+
+The opacity of the webview (0-1).
+Defaults to `1`.
+
+### `.{...Node}`
+
+Inherits all [Node](/docs/scripting/nodes/Node.md) properties including position, rotation, scale, etc.
+
+## Examples
+
+### YouTube Video Screen
+
+```jsx
+const tvScreen = app.create('webview', {
+  src: 'https://www.youtube.com/embed/dQw4w9WgXcQ',
+  width: 1920,
+  height: 1080,
+  space: 'world',
+  size: 0.002
+})
+tvScreen.position.set(0, 3, -8)
+app.add(tvScreen)
+```
+
+### HUD Mini-Map
+
+```jsx
+const minimap = app.create('webview', {
+  src: 'https://example.com/minimap',
+  width: 200,
+  height: 200,
+  space: 'screen',
+  opacity: 0.8
+})
+// Position in top-right corner
+minimap.position.set(0.85, 0.15, 0)
+app.add(minimap)
+```
+
+### Information Panel
+
+```jsx
+const infoPanel = app.create('webview', {
+  src: 'https://example.com/info',
+  width: 600,
+  height: 400,
+  space: 'world',
+  size: 0.005
+})
+infoPanel.position.set(5, 2, 0)
+app.add(infoPanel)
+```
+
+## Current Limitations
+
+1. **Overlay Rendering**: WebViews render as DOM overlays on top of the 3D scene
+2. **No Depth Testing**: WebViews appear on top of all 3D objects
+3. **Performance**: Multiple webviews may impact performance
+4. **Mobile Support**: May have limited functionality on mobile devices
+5. **Interaction**: Direct mouse/touch interaction (not reticle-based in world space)
+
+## Security
+
+Currently all URLs are allowed for development. In production, consider implementing:
+- Domain allowlisting
+- HTTPS-only content
+- Sandbox attributes for iframes
+- Content Security Policy (CSP)