docs: improve clarity of setup instructions

[claudeaceae]

Summary

This PR improves the setup documentation with clearer instructions and up-to-date version information:

• Updated Chrome version requirement from 144 to 145 (now in stable channel as of December 2024)
• Added clearer distinction between automatic vs manual connection methods
• Improved grammar consistency throughout
• Added helpful note about when to use beta/canary channels
• Added nvm usage example in contributing guide for easier Node.js version management

Changes

All changes are documentation-only:

• /tmp/chrome-mcp/README.md - Updated Chrome version info and improved connection method descriptions
• /tmp/chrome-mcp/CONTRIBUTING.md - Added nvm usage tip for contributors

These improvements help users:

1. Choose the right connection method for their use case
2. Understand current Chrome version requirements
3. Get started more easily with the correct Node.js version

🤖 Generated with Claude Code

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