Make a pass through the docs/deployment.md file to hopefully improve readability and conciseness
Notably, I've proposed axing both the "Core Features" section - which feels too promotional this far down the folder hierarchy and which is somewhat repetitive to later in the page - and the "Basic Interaction" section - which is covered better, and makes more sense, in other parts of the documentation
This commit adds a new `tutorials.md` file to the CLI documentation.
This section is intended to house various tutorials for using Gemini CLI.
The initial content includes a tutorial on setting up Model Context
Protocol (MCP) servers, using the GitHub MCP server as an example.
The `docs/cli/index.md` has been updated to include a link to this
new tutorials section.
