Move the package to "lit" project

I think, currently, your tool is only one on github which allows to integrate `stylelint` in lit-related project (except maybe some potentially existing custom local plugins in some repos). Are there plans maybe to propose storing your tool as a recommended solution in `lit` project? It's already mentioned in `stylelint` [docs](https://stylelint.io/developer-guide/syntaxes/), would be better to mention it as a recommend way in postcss repo as well.

The issue suggests proposing the postcss-lit package as a recommended solution in the lit project. First, understand the current integration with stylelint and how postcss-lit works by reading its README and source code. Then, research the lit project's contribution guidelines and existing recommended tools to see how to propose inclusion. The goal is to prepare a proposal or documentation update for the lit project, not to change code in postcss-lit itself.

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