* feat(tools): merge some tools into the `air` CLI tool
`air-beautify` and `air-trace` are merged into a single `air` tool. Its
crate name is `fluence-air-cli` as otherwise it confilicts with `air`
interpreter crate. The tool has subcommands `beautify`, `run`
and `stats`.
* Add one-letter aliases to `air` CLI subcommands
+ `air beautify` => `air b`
+ `air run` => `air r`
+ `air stats` => `air s`
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Co-authored-by: Mike Voronov <michail.vms@gmail.com>
Intially, a fold instruction was designed based on idea that its iterable can't expand,
so AIR was considered as a subtree. But after introducing recursive streams in #225, it's
no more a subtree, but a subgraph.
