docs: boilerplate v10 readme

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Please verify the following:

• yarn test jest tests pass with new tests, if relevant
• yarn lint eslint checks pass with new code, if relevant
• yarn format:check prettier checks pass with new code, if relevant
• README.md (or relevant documentation) has been updated with your changes
• If this affects functionality there aren't tests for, I manually tested it, including by generating a new app locally if needed (see docs).

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