Kernel SDK: decouple installer creation from DAC node

Context

Previously, to generate a kernel installer, you had to run the DAC node. This MR adds a smart-rollup-installer client binary, to generate the installer binary, and the kernel preimages, from pure rust.

To do so, it leverages 'wasm custom sections' to be able to write arbitrary configurations to the installer kernel. (For now, only the root_hash for the installee is written)

Manually testing the MR

make -f kernels.mk build-kernels
dune exec tezt/tests/main.exe -- --file tx_sc_rollup.ml
dune exec tezt/tests/main.exe -- --file evm_rollup.ml

requires

• kernel!150 (closed)
• kernel!153 (closed)

Install the tool (try pointing at a random file for example):

export PATH=$PATH:$HOME/.cargo/bin

cargo install tezos_smart_rollup_installer --git https://gitlab.com/tezos/tezos --branch emturner@installer-tezt

smart-rollup-installer get-reveal-installer --upgrade-to <file> --output installer.hex --preimages-dir /tmp/installer

You should see a few files in tmp/installer, and a new installer.hex in your local directory.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR