docs: S2 migration docs and codemod setup (#6828)
* initialize migration docs
* more docs for Item updates
* move upgrade-cli to codemods package
* improve rendered diffs
* setup codemod entry
* update yarn.lock
* fix component index path resolving
* update package.json
* update yarn.lock
* move to src
* update component index path
* update lock file
* fix ts
* update command in docs
* fix --components option for providing a subset of components to upgrade
* update docs to not collapse manual guide
* update index to use parseArgs and pass args into codemod functions
* just rely on require.resolve to get S2 index path
* remove commander dep
* move use-monopackages codemod into new package
* update @react-spectrum/s2 dep
* update yarn.lock
* fix types and update use-monopackages readme
* try removing main from package.json
* use path module
* use moduleResolution in tsconfig
* remove module.exports
* try renaming transformer functions
* Revert "try renaming transformer functions"
This reverts commit b2177f7621a8067a2539b8bdcc13ab717da38e42.
* try targets: main: false in package.json
* move to packages/dev
* update docs
* add anchor links
* update yarn.lock
* fix anchor links in built docs
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Co-authored-by: Robert Snow <rsnow@adobe.com>
