feat(screenshot): add JPEG quality parameter support

[Coquinate]

Summary

This PR adds support for the quality parameter when taking JPEG screenshots, allowing users to control compression levels and significantly reduce file sizes.

Problem

Currently, the Chrome DevTools MCP doesn't expose the quality parameter that Puppeteer natively supports. This leads to:

• Large screenshot file sizes (especially problematic for AI assistants with image size limits)
• No control over JPEG compression
• Inability to optimize screenshots for different use cases

Solution

Added the quality parameter (0-100) to the screenshot tool schema and passed it through to Puppeteer's screenshot method.

Changes

• ✅ Added quality parameter to screenshot schema with proper validation (0-100 range)
• ✅ Pass quality parameter to Puppeteer's screenshot() method
• ✅ Added optimizeForSpeed flag for improved encoding performance
• ✅ Updated documentation via npm run docs

Testing

Tested locally with various quality settings:

• PNG (baseline): 128 KB
• JPEG quality 100: 245 KB
• JPEG quality 50: 84 KB (35% reduction)
• JPEG quality 30: 66 KB (49% reduction)

Impact

This change is backward compatible - the quality parameter is optional and doesn't affect existing usage. It particularly helps with:

• AI assistants that have image size limits (e.g., 8000px max dimension errors)
• Reducing bandwidth when capturing many screenshots
• Optimizing storage for screenshot-heavy workflows

Example Usage

// New capability - control JPEG quality
await take_screenshot({
  format: 'jpeg',
  quality: 50,  // New parameter!
  fullPage: false
})

Checklist

• Code follows conventional commits
• Documentation updated with npm run docs
• Tested locally
• Backward compatible
• CLA signed (will complete if needed)

Fixes #[issue-number] (if applicable)

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