allow responsive viewport size

[EarthmanWeb]

Add Responsive Viewport Mode

Summary

Adds a responsive parameter to browser_create_instance that passes null viewport to Playwright, enabling freely resizable browser windows for responsive layout testing.

Problem

The upstream MCP hardcodes viewport to {width: 1280, height: 720}, preventing:

• Testing responsive layouts
• Resizing browser windows freely
• Matching real user viewport conditions

Solution

When responsive: true is passed, viewport is set to null in Playwright.

Changes

File	Change
src/types.ts	viewport accepts null, added responsive?: boolean
src/tools.ts	Added responsive param to schema, passes null when enabled
src/browser-manager.ts	Returns responsive: true in response data

Usage

// Responsive mode - window freely resizable
browser_create_instance({ headless: false, responsive: true })
// Returns: { viewport: null, responsive: true, ... }

// Fixed mode (default) - 1280x720
browser_create_instance({ headless: false })
// Returns: { viewport: { width: 1280, height: 720 }, ... }