This adds a structure and some basic functionality for the Flame
devtools extension.
Later I will add a pre/post-hook for publishing to Melos so that it can
build the devtools extension before publishing (and remove the directory
afterwards), since it isn't committed to this repository. For now one
has to run `melos devtools-build` before publishing.
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Co-authored-by: Renan <6718144+renancaraujo@users.noreply.github.com>
Co-authored-by: Erick <erickzanardoo@gmail.com>
