gatsby-theme-mini | : memo : : art : A theme for blog based on Gatsby | Static Site Generator library

There are two concepts that is used in your question.

1. The directory name of the workspace. To change it just rename the directory and update workspaces field to refer to the new directory name
2. The package name of the workspace - it is provided in package.json inside name field for the corresponding workspace. For gatsby-theme-minimal it is provided inside gatsby-theme-minimal/package.json -> name. Just edit package.json and change the name.

After making changes via 1) or 2) or both of them you need to run yarn in order for Yarn to update any installation files that refer to them. If you change workspace package name as per 2) you should also edit and update any code that requires/imports workspace by the old package name.

Gatsby theme shadowing only applies to files in the src directory and deeper. You should be able to control page creation from gatsby-node.js in the root of your project though. If that file does not already exist, create one. Duplicate the code you want to change from the core themes gatsby-node.js and modify it in the gatsby-node.js in your project root.