Improve README formatting and English writing

[PabloLION]

Updates the README.md file of the xterm-react project to improve readability, correct typos, and enhance documentation.

• Corrects Typos: Fixes the specific typo from blur() to .blur() to accurately reflect the method call.
• Improves English Writing: Enhances the clarity and readability of the text, making it easier to understand for readers.
• Reformats Document: Organizes the content into more distinct sections and utilizes markdown features for better structure and presentation, including headings, code blocks, and lists.
• Enhances Documentation: Updates the documentation to align with the latest @xterm/xterm library, introduces new sections like Installation, Usage, Props, Development, Contributing, and License for comprehensive guidance.
• Code Style and Functionality: Discusses improvements in code style, such as adopting consistent naming conventions and exposing more methods directly from the XTerm class. Also highlights the addition of new functionality like event listeners and terminal methods.

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For more details, open the Copilot Workspace session.