Add a skill for creating a new project

[jakemac53]

We are planning to disable the flutter create tool in the MCP server, but @mariamhas noted that agents don't reliably just run flutter create.

We could also include instructions to get the package layout set down a good direction with some general organization guidelines etc.

[Barry0501]

Hi team! I just wanted to say a huge thanks for starting this flutter/skills initiative—it's such a brilliant way to standardize AI-ready knowledge for the community and I'm really excited to be part of it.

I've just submitted PR #51 to address this issue. It covers the 'Creating a New Project' skill with comprehensive CLI and IDE workflows. Would love to get your thoughts on it