Add missing tools and parameters to MCP sever docs

What does this MR do and why?

The documentation for the GitLab MCP sever does not list all available tools and properties. This MR adds the following to each MCP sever tool:

• Some missing parameters and their descriptions
• The type of each parameter

Also, this MR fixes the names of two tools that have been updated in the meantime.

For a full list of tools and parameters, see https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/spec/requests/api/mcp/handlers/list_tools_spec.rb.

References

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Before	After

How to set up and validate locally

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