add prettier, move most markdown into `docs/` and add a packagers guide
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* lint(md): add prettier
* docs(packagers): add a guide
* docs(correctness): Index -> ToC
* docs: link to package maintainers guide
* docs: move install docs to `./docs`
* docs(fix): typo
* docs(typo): fix typo in Contributing.md
* add optional PAM service name
* feat(PAM service name): Add ENV variable configuration for the PAM service name
* feat(PAM service name): Implement suggested changes + update README instructions
* docs(remove segment)