Add placeholder landing page for GPT project

[Copilot]

The repository lacked a clear landing page. This PR adds an engaging README.md that provides context for visitors familiar with GPTs while the project is under development.

Changes

• README.md: Updated with welcoming content that references OpenAI's Introducing GPTs, emphasizes the repository as an innovative development space, and explicitly states this is a temporary placeholder
• Preserved original project motto and domain at bottom

Result

# Welcome to the GPT Project! 🚀

## An Innovative Space for Ongoing Development

Welcome! If you're here, you're likely already familiar with the exciting world of GPTs...

Visitors now see a professional landing page instead of minimal content.

Original prompt

The LuxciumProject/gpt repository currently lacks a clear landing page. Please create a README.md file or update the existing one to serve as a placeholder landing page. The content should resonate with users already familiar with GPTs, referencing OpenAI's Introducing GPTs to provide general context. Ensure that the tone is engaging, emphasizes excitement about the project, and highlights that the repository will serve as an innovative space for ongoing development. Avoid making assumptions about contributions or technical details. State that the page serves as a temporary placeholder until more content is added.

This pull request was created as a result of the following prompt from Copilot chat.

The LuxciumProject/gpt repository currently lacks a clear landing page. Please create a README.md file or update the existing one to serve as a placeholder landing page. The content should resonate with users already familiar with GPTs, referencing OpenAI's Introducing GPTs to provide general context. Ensure that the tone is engaging, emphasizes excitement about the project, and highlights that the repository will serve as an innovative space for ongoing development. Avoid making assumptions about contributions or technical details. State that the page serves as a temporary placeholder until more content is added.

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